CVE-2023-3255 (GCVE-0-2023-3255)

Vulnerability from cvelistv5 – Published: 2023-09-13 16:12 – Updated: 2026-11-01 03:01
VLAI
Title
Qemu: vnc: infinite loop in inflate_buffer() leads to denial of service
Summary
A flaw was found in the QEMU built-in VNC server while processing ClientCutText messages. A wrong exit condition may lead to an infinite loop when inflating an attacker controlled zlib buffer in the `inflate_buffer` function. This could allow a remote authenticated client who is able to send a clipboard to the VNC server to trigger a denial of service.
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2025-10-17 17:14 UTC
CWE
  • CWE-835 - Loop with Unreachable Exit Condition
Assigner
redhat CNA under the redhat root
CNA scorecard B 82/100 over 1089 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Red Hat Red Hat Enterprise Linux 8 Unaffected: 8100020240314161907.e155f54d , < * (rpm)
    cpe:/a:redhat:enterprise_linux:8::appstream
    cpe:/a:redhat:enterprise_linux:8::crb
Create a notification for this product.
Red Hat Red Hat Enterprise Linux 9 Unaffected: 17:8.2.0-11.el9_4 , < * (rpm)
    cpe:/a:redhat:enterprise_linux:9::appstream
Create a notification for this product.
Red Hat Red Hat Enterprise Linux 6     cpe:/o:redhat:enterprise_linux:6
Create a notification for this product.
Red Hat Red Hat Enterprise Linux 7     cpe:/o:redhat:enterprise_linux:7
Create a notification for this product.
Red Hat Red Hat Enterprise Linux 8 Advanced Virtualization     cpe:/a:redhat:advanced_virtualization:8::el8
Create a notification for this product.
Date Public
2023-07-04 00:00
Show details on NVD website

{
  "containers": {
    "adp": [
      {
        "providerMetadata": {
          "dateUpdated": "2024-08-02T06:48:08.172Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
          "shortName": "CVE"
        },
        "references": [
          {
            "name": "RHSA-2024:2135",
            "tags": [
              "vendor-advisory",
              "x_refsource_REDHAT",
              "x_transferred"
            ],
            "url": "https://access.redhat.com/errata/RHSA-2024:2135"
          },
          {
            "name": "RHSA-2024:2962",
            "tags": [
              "vendor-advisory",
              "x_refsource_REDHAT",
              "x_transferred"
            ],
            "url": "https://access.redhat.com/errata/RHSA-2024:2962"
          },
          {
            "tags": [
              "vdb-entry",
              "x_refsource_REDHAT",
              "x_transferred"
            ],
            "url": "https://access.redhat.com/security/cve/CVE-2023-3255"
          },
          {
            "name": "RHBZ#2218486",
            "tags": [
              "issue-tracking",
              "x_refsource_REDHAT",
              "x_transferred"
            ],
            "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2218486"
          },
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://security.netapp.com/advisory/ntap-20231020-0008/"
          }
        ],
        "title": "CVE Program Container"
      },
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2023-3255",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2025-10-17T17:14:24.314787Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2025-10-17T17:14:32.839Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "cpes": [
            "cpe:/a:redhat:enterprise_linux:8::appstream",
            "cpe:/a:redhat:enterprise_linux:8::crb"
          ],
          "defaultStatus": "affected",
          "packageName": "virt-devel:rhel",
          "product": "Red Hat Enterprise Linux 8",
          "vendor": "Red Hat",
          "versions": [
            {
              "lessThan": "*",
              "status": "unaffected",
              "version": "8100020240314161907.e155f54d",
              "versionType": "rpm"
            }
          ]
        },
        {
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "cpes": [
            "cpe:/a:redhat:enterprise_linux:8::appstream",
            "cpe:/a:redhat:enterprise_linux:8::crb"
          ],
          "defaultStatus": "affected",
          "packageName": "virt:rhel",
          "product": "Red Hat Enterprise Linux 8",
          "vendor": "Red Hat",
          "versions": [
            {
              "lessThan": "*",
              "status": "unaffected",
              "version": "8100020240314161907.e155f54d",
              "versionType": "rpm"
            }
          ]
        },
        {
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "cpes": [
            "cpe:/a:redhat:enterprise_linux:9::appstream"
          ],
          "defaultStatus": "affected",
          "packageName": "qemu-kvm",
          "product": "Red Hat Enterprise Linux 9",
          "vendor": "Red Hat",
          "versions": [
            {
              "lessThan": "*",
              "status": "unaffected",
              "version": "17:8.2.0-11.el9_4",
              "versionType": "rpm"
            }
          ]
        },
        {
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "cpes": [
            "cpe:/o:redhat:enterprise_linux:6"
          ],
          "defaultStatus": "unaffected",
          "packageName": "qemu-kvm",
          "product": "Red Hat Enterprise Linux 6",
          "vendor": "Red Hat"
        },
        {
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "cpes": [
            "cpe:/o:redhat:enterprise_linux:7"
          ],
          "defaultStatus": "unaffected",
          "packageName": "qemu-kvm",
          "product": "Red Hat Enterprise Linux 7",
          "vendor": "Red Hat"
        },
        {
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "cpes": [
            "cpe:/o:redhat:enterprise_linux:7"
          ],
          "defaultStatus": "unaffected",
          "packageName": "qemu-kvm-ma",
          "product": "Red Hat Enterprise Linux 7",
          "vendor": "Red Hat"
        },
        {
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "cpes": [
            "cpe:/a:redhat:advanced_virtualization:8::el8"
          ],
          "defaultStatus": "unaffected",
          "packageName": "virt:av/qemu-kvm",
          "product": "Red Hat Enterprise Linux 8 Advanced Virtualization",
          "vendor": "Red Hat"
        }
      ],
      "credits": [
        {
          "lang": "en",
          "value": "Red Hat would like to thank Kevin Denis (Synacktiv) for reporting this issue."
        }
      ],
      "datePublic": "2023-07-04T00:00:00.000Z",
      "descriptions": [
        {
          "lang": "en",
          "value": "A flaw was found in the QEMU built-in VNC server while processing ClientCutText messages. A wrong exit condition may lead to an infinite loop when inflating an attacker controlled zlib buffer in the `inflate_buffer` function. This could allow a remote authenticated client who is able to send a clipboard to the VNC server to trigger a denial of service."
        }
      ],
      "metrics": [
        {
          "other": {
            "content": {
              "namespace": "https://access.redhat.com/security/updates/classification/",
              "value": "Moderate"
            },
            "type": "Red Hat severity rating"
          }
        },
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 6.5,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "NONE",
            "integrityImpact": "NONE",
            "privilegesRequired": "LOW",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
            "version": "3.1"
          },
          "format": "CVSS"
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-835",
              "description": "Loop with Unreachable Exit Condition",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-11-01T03:01:56.984Z",
        "orgId": "53f830b8-0a3f-465b-8143-3b8a9948e749",
        "shortName": "redhat"
      },
      "references": [
        {
          "name": "RHSA-2024:2135",
          "tags": [
            "vendor-advisory",
            "x_refsource_REDHAT"
          ],
          "url": "https://access.redhat.com/errata/RHSA-2024:2135"
        },
        {
          "name": "RHSA-2024:2962",
          "tags": [
            "vendor-advisory",
            "x_refsource_REDHAT"
          ],
          "url": "https://access.redhat.com/errata/RHSA-2024:2962"
        },
        {
          "tags": [
            "vdb-entry",
            "x_refsource_REDHAT"
          ],
          "url": "https://access.redhat.com/security/cve/CVE-2023-3255"
        },
        {
          "name": "RHBZ#2218486",
          "tags": [
            "issue-tracking",
            "x_refsource_REDHAT"
          ],
          "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2218486"
        }
      ],
      "timeline": [
        {
          "lang": "en",
          "time": "2023-06-28T00:00:00.000Z",
          "value": "Reported to Red Hat."
        },
        {
          "lang": "en",
          "time": "2023-07-04T00:00:00.000Z",
          "value": "Made public."
        }
      ],
      "title": "Qemu: vnc: infinite loop in inflate_buffer() leads to denial of service",
      "x_generator": {
        "engine": "cvelib 1.8.0"
      },
      "x_redhatCweChain": "CWE-835: Loop with Unreachable Exit Condition"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "53f830b8-0a3f-465b-8143-3b8a9948e749",
    "assignerShortName": "redhat",
    "cveId": "CVE-2023-3255",
    "datePublished": "2023-09-13T16:12:52.294Z",
    "dateReserved": "2023-06-14T21:08:31.376Z",
    "dateUpdated": "2026-11-01T03:01:56.984Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2023-3255",
      "date": "2026-11-04",
      "epss": "0.01891",
      "percentile": "0.7963"
    },
    "fkie_nvd": {
      "configurations": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:a:qemu:qemu:*:*:*:*:*:*:*:*",
                  "matchCriteriaId": "445665D6-88FF-45C2-BB87-34AB7A72A7BF",
                  "versionEndIncluding": "8.0.3",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        },
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*",
                  "matchCriteriaId": "F4CFF558-3C47-480D-A2F0-BABF26042943",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:redhat:enterprise_linux:9.0:*:*:*:*:*:*:*",
                  "matchCriteriaId": "7F6FB57C-2BC7-487C-96DD-132683AEB35D",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        },
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:fedoraproject:fedora:38:*:*:*:*:*:*:*",
                  "matchCriteriaId": "CC559B26-5DFC-4B7A-A27C-B77DE755DFF9",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "A flaw was found in the QEMU built-in VNC server while processing ClientCutText messages. A wrong exit condition may lead to an infinite loop when inflating an attacker controlled zlib buffer in the `inflate_buffer` function. This could allow a remote authenticated client who is able to send a clipboard to the VNC server to trigger a denial of service."
        },
        {
          "lang": "es",
          "value": "Se encontr\u00f3 una falla en el servidor VNC integrado de QEMU al procesar mensajes ClientCutText. Una condici\u00f3n de salida incorrecta puede provocar un bucle infinito al inflar un b\u00fafer zlib controlado por un atacante en la funci\u00f3n `inflate_buffer`. Esto podr\u00eda permitir que un cliente remoto autenticado que pueda enviar un portapapeles al servidor VNC active una denegaci\u00f3n de servicio."
        }
      ],
      "id": "CVE-2023-3255",
      "lastModified": "2024-11-21T08:16:48.617",
      "metrics": {
        "cvssMetricV31": [
          {
            "cvssData": {
              "attackComplexity": "LOW",
              "attackVector": "NETWORK",
              "availabilityImpact": "HIGH",
              "baseScore": 6.5,
              "baseSeverity": "MEDIUM",
              "confidentialityImpact": "NONE",
              "integrityImpact": "NONE",
              "privilegesRequired": "LOW",
              "scope": "UNCHANGED",
              "userInteraction": "NONE",
              "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
              "version": "3.1"
            },
            "exploitabilityScore": 2.8,
            "impactScore": 3.6,
            "source": "secalert@redhat.com",
            "type": "Secondary"
          },
          {
            "cvssData": {
              "attackComplexity": "LOW",
              "attackVector": "NETWORK",
              "availabilityImpact": "HIGH",
              "baseScore": 6.5,
              "baseSeverity": "MEDIUM",
              "confidentialityImpact": "NONE",
              "integrityImpact": "NONE",
              "privilegesRequired": "LOW",
              "scope": "UNCHANGED",
              "userInteraction": "NONE",
              "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
              "version": "3.1"
            },
            "exploitabilityScore": 2.8,
            "impactScore": 3.6,
            "source": "nvd@nist.gov",
            "type": "Primary"
          }
        ]
      },
      "published": "2023-09-13T17:15:09.877",
      "references": [
        {
          "source": "secalert@redhat.com",
          "url": "https://access.redhat.com/errata/RHSA-2024:2135"
        },
        {
          "source": "secalert@redhat.com",
          "url": "https://access.redhat.com/errata/RHSA-2024:2962"
        },
        {
          "source": "secalert@redhat.com",
          "tags": [
            "Third Party Advisory"
          ],
          "url": "https://access.redhat.com/security/cve/CVE-2023-3255"
        },
        {
          "source": "secalert@redhat.com",
          "tags": [
            "Issue Tracking",
            "Patch",
            "Third Party Advisory"
          ],
          "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2218486"
        },
        {
          "source": "af854a3a-2127-422b-91ae-364da2661108",
          "url": "https://access.redhat.com/errata/RHSA-2024:2135"
        },
        {
          "source": "af854a3a-2127-422b-91ae-364da2661108",
          "url": "https://access.redhat.com/errata/RHSA-2024:2962"
        },
        {
          "source": "af854a3a-2127-422b-91ae-364da2661108",
          "tags": [
            "Third Party Advisory"
          ],
          "url": "https://access.redhat.com/security/cve/CVE-2023-3255"
        },
        {
          "source": "af854a3a-2127-422b-91ae-364da2661108",
          "tags": [
            "Issue Tracking",
            "Patch",
            "Third Party Advisory"
          ],
          "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2218486"
        },
        {
          "source": "af854a3a-2127-422b-91ae-364da2661108",
          "url": "https://security.netapp.com/advisory/ntap-20231020-0008/"
        }
      ],
      "sourceIdentifier": "secalert@redhat.com",
      "vulnStatus": "Modified",
      "weaknesses": [
        {
          "description": [
            {
              "lang": "en",
              "value": "CWE-835"
            }
          ],
          "source": "secalert@redhat.com",
          "type": "Secondary"
        },
        {
          "description": [
            {
              "lang": "en",
              "value": "CWE-835"
            }
          ],
          "source": "nvd@nist.gov",
          "type": "Primary"
        }
      ]
    },
    "microsoft_vex": {
      "current_release_date": "2026-02-18T01:45:38.000Z",
      "cve": "CVE-2023-3255",
      "id": "msrc_CVE-2023-3255",
      "initial_release_date": "2023-09-01T00:00:00.000Z",
      "product_status:fixed": "3",
      "product_status:known_affected": "3",
      "source": "Microsoft CSAF VEX",
      "status": "final",
      "title": "Qemu: vnc: infinite loop in inflate_buffer() leads to denial of service",
      "url": "https://msrc.microsoft.com/csaf/vex/2023/msrc_cve-2023-3255.json",
      "version": "3"
    },
    "nvd": {
      "cve": {
        "affected": [
          {
            "affectedData": [
              {
                "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
                "cpes": [
                  "cpe:/a:redhat:enterprise_linux:8::appstream",
                  "cpe:/a:redhat:enterprise_linux:8::crb"
                ],
                "defaultStatus": "affected",
                "packageName": "virt-devel:rhel",
                "product": "Red Hat Enterprise Linux 8",
                "vendor": "Red Hat",
                "versions": [
                  {
                    "lessThan": "*",
                    "status": "unaffected",
                    "version": "8100020240314161907.e155f54d",
                    "versionType": "rpm"
                  }
                ]
              },
              {
                "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
                "cpes": [
                  "cpe:/a:redhat:enterprise_linux:8::appstream",
                  "cpe:/a:redhat:enterprise_linux:8::crb"
                ],
                "defaultStatus": "affected",
                "packageName": "virt:rhel",
                "product": "Red Hat Enterprise Linux 8",
                "vendor": "Red Hat",
                "versions": [
                  {
                    "lessThan": "*",
                    "status": "unaffected",
                    "version": "8100020240314161907.e155f54d",
                    "versionType": "rpm"
                  }
                ]
              },
              {
                "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
                "cpes": [
                  "cpe:/a:redhat:enterprise_linux:9::appstream"
                ],
                "defaultStatus": "affected",
                "packageName": "qemu-kvm",
                "product": "Red Hat Enterprise Linux 9",
                "vendor": "Red Hat",
                "versions": [
                  {
                    "lessThan": "*",
                    "status": "unaffected",
                    "version": "17:8.2.0-11.el9_4",
                    "versionType": "rpm"
                  }
                ]
              },
              {
                "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
                "cpes": [
                  "cpe:/o:redhat:enterprise_linux:6"
                ],
                "defaultStatus": "unaffected",
                "packageName": "qemu-kvm",
                "product": "Red Hat Enterprise Linux 6",
                "vendor": "Red Hat"
              },
              {
                "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
                "cpes": [
                  "cpe:/o:redhat:enterprise_linux:7"
                ],
                "defaultStatus": "unaffected",
                "packageName": "qemu-kvm",
                "product": "Red Hat Enterprise Linux 7",
                "vendor": "Red Hat"
              },
              {
                "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
                "cpes": [
                  "cpe:/o:redhat:enterprise_linux:7"
                ],
                "defaultStatus": "unaffected",
                "packageName": "qemu-kvm-ma",
                "product": "Red Hat Enterprise Linux 7",
                "vendor": "Red Hat"
              },
              {
                "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
                "cpes": [
                  "cpe:/a:redhat:advanced_virtualization:8::el8"
                ],
                "defaultStatus": "unaffected",
                "packageName": "virt:av/qemu-kvm",
                "product": "Red Hat Enterprise Linux 8 Advanced Virtualization",
                "vendor": "Red Hat"
              }
            ],
            "source": "secalert@redhat.com"
          }
        ],
        "configurations": [
          {
            "nodes": [
              {
                "cpeMatch": [
                  {
                    "criteria": "cpe:2.3:a:qemu:qemu:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "445665D6-88FF-45C2-BB87-34AB7A72A7BF",
                    "versionEndIncluding": "8.0.3",
                    "vulnerable": true
                  }
                ],
                "negate": false,
                "operator": "OR"
              }
            ]
          },
          {
            "nodes": [
              {
                "cpeMatch": [
                  {
                    "criteria": "cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*",
                    "matchCriteriaId": "F4CFF558-3C47-480D-A2F0-BABF26042943",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:redhat:enterprise_linux:9.0:*:*:*:*:*:*:*",
                    "matchCriteriaId": "7F6FB57C-2BC7-487C-96DD-132683AEB35D",
                    "vulnerable": true
                  }
                ],
                "negate": false,
                "operator": "OR"
              }
            ]
          },
          {
            "nodes": [
              {
                "cpeMatch": [
                  {
                    "criteria": "cpe:2.3:o:fedoraproject:fedora:38:*:*:*:*:*:*:*",
                    "matchCriteriaId": "CC559B26-5DFC-4B7A-A27C-B77DE755DFF9",
                    "vulnerable": true
                  }
                ],
                "negate": false,
                "operator": "OR"
              }
            ]
          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "A flaw was found in the QEMU built-in VNC server while processing ClientCutText messages. A wrong exit condition may lead to an infinite loop when inflating an attacker controlled zlib buffer in the `inflate_buffer` function. This could allow a remote authenticated client who is able to send a clipboard to the VNC server to trigger a denial of service."
          },
          {
            "lang": "es",
            "value": "Se encontr\u00f3 una falla en el servidor VNC integrado de QEMU al procesar mensajes ClientCutText. Una condici\u00f3n de salida incorrecta puede provocar un bucle infinito al inflar un b\u00fafer zlib controlado por un atacante en la funci\u00f3n `inflate_buffer`. Esto podr\u00eda permitir que un cliente remoto autenticado que pueda enviar un portapapeles al servidor VNC active una denegaci\u00f3n de servicio."
          }
        ],
        "id": "CVE-2023-3255",
        "lastModified": "2026-06-17T06:13:41.063",
        "metrics": {
          "cvssMetricV31": [
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "NETWORK",
                "availabilityImpact": "HIGH",
                "baseScore": 6.5,
                "baseSeverity": "MEDIUM",
                "confidentialityImpact": "NONE",
                "integrityImpact": "NONE",
                "privilegesRequired": "LOW",
                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
                "version": "3.1"
              },
              "exploitabilityScore": 2.8,
              "impactScore": 3.6,
              "source": "secalert@redhat.com",
              "type": "Secondary"
            },
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "NETWORK",
                "availabilityImpact": "HIGH",
                "baseScore": 6.5,
                "baseSeverity": "MEDIUM",
                "confidentialityImpact": "NONE",
                "integrityImpact": "NONE",
                "privilegesRequired": "LOW",
                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
                "version": "3.1"
              },
              "exploitabilityScore": 2.8,
              "impactScore": 3.6,
              "source": "nvd@nist.gov",
              "type": "Primary"
            }
          ],
          "ssvcV203": [
            {
              "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
              "ssvcData": {
                "id": "CVE-2023-3255",
                "options": [
                  {
                    "exploitation": "none"
                  },
                  {
                    "automatable": "no"
                  },
                  {
                    "technicalImpact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2025-10-17T17:14:24.314787Z",
                "version": "2.0.3"
              }
            }
          ]
        },
        "published": "2023-09-13T17:15:09.877",
        "references": [
          {
            "source": "secalert@redhat.com",
            "url": "https://access.redhat.com/errata/RHSA-2024:2135"
          },
          {
            "source": "secalert@redhat.com",
            "url": "https://access.redhat.com/errata/RHSA-2024:2962"
          },
          {
            "source": "secalert@redhat.com",
            "tags": [
              "Third Party Advisory"
            ],
            "url": "https://access.redhat.com/security/cve/CVE-2023-3255"
          },
          {
            "source": "secalert@redhat.com",
            "tags": [
              "Issue Tracking",
              "Patch",
              "Third Party Advisory"
            ],
            "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2218486"
          },
          {
            "source": "af854a3a-2127-422b-91ae-364da2661108",
            "url": "https://access.redhat.com/errata/RHSA-2024:2135"
          },
          {
            "source": "af854a3a-2127-422b-91ae-364da2661108",
            "url": "https://access.redhat.com/errata/RHSA-2024:2962"
          },
          {
            "source": "af854a3a-2127-422b-91ae-364da2661108",
            "tags": [
              "Third Party Advisory"
            ],
            "url": "https://access.redhat.com/security/cve/CVE-2023-3255"
          },
          {
            "source": "af854a3a-2127-422b-91ae-364da2661108",
            "tags": [
              "Issue Tracking",
              "Patch",
              "Third Party Advisory"
            ],
            "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2218486"
          },
          {
            "source": "af854a3a-2127-422b-91ae-364da2661108",
            "url": "https://security.netapp.com/advisory/ntap-20231020-0008/"
          }
        ],
        "sourceIdentifier": "secalert@redhat.com",
        "vulnStatus": "Modified",
        "weaknesses": [
          {
            "description": [
              {
                "lang": "en",
                "value": "CWE-835"
              }
            ],
            "source": "secalert@redhat.com",
            "type": "Secondary"
          },
          {
            "description": [
              {
                "lang": "en",
                "value": "CWE-835"
              }
            ],
            "source": "nvd@nist.gov",
            "type": "Primary"
          }
        ]
      }
    },
    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-11-01T03:23:21+00:00",
      "cve": "CVE-2023-3255",
      "id": "CVE-2023-3255",
      "initial_release_date": "2023-07-04T00:00:00+00:00",
      "product_status:fixed": "1054",
      "product_status:known_not_affected": "37",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "QEMU: VNC: infinite loop in inflate_buffer() leads to denial of service",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2023/cve-2023-3255.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "moderate",
      "current_release_date": "2026-10-16T13:59:08Z",
      "cve": "CVE-2023-3255",
      "id": "CVE-2023-3255",
      "initial_release_date": "2023-07-07T02:19:30Z",
      "product_status:known_affected": "394",
      "product_status:known_not_affected": "935",
      "product_status:recommended": "1272",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2023-3255",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/2023/cve-2023-3255.json",
      "version": "57"
    },
    "vulnrichment": {
      "containers": {
        "adp": [
          {
            "providerMetadata": {
              "dateUpdated": "2024-08-02T06:48:08.172Z",
              "orgId": "af854a3a-2127-422b-91ae-364da2661108",
              "shortName": "CVE"
            },
            "references": [
              {
                "name": "RHSA-2024:2135",
                "tags": [
                  "vendor-advisory",
                  "x_refsource_REDHAT",
                  "x_transferred"
                ],
                "url": "https://access.redhat.com/errata/RHSA-2024:2135"
              },
              {
                "name": "RHSA-2024:2962",
                "tags": [
                  "vendor-advisory",
                  "x_refsource_REDHAT",
                  "x_transferred"
                ],
                "url": "https://access.redhat.com/errata/RHSA-2024:2962"
              },
              {
                "tags": [
                  "vdb-entry",
                  "x_refsource_REDHAT",
                  "x_transferred"
                ],
                "url": "https://access.redhat.com/security/cve/CVE-2023-3255"
              },
              {
                "name": "RHBZ#2218486",
                "tags": [
                  "issue-tracking",
                  "x_refsource_REDHAT",
                  "x_transferred"
                ],
                "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2218486"
              },
              {
                "tags": [
                  "x_transferred"
                ],
                "url": "https://security.netapp.com/advisory/ntap-20231020-0008/"
              }
            ],
            "title": "CVE Program Container"
          },
          {
            "metrics": [
              {
                "other": {
                  "content": {
                    "id": "CVE-2023-3255",
                    "options": [
                      {
                        "Exploitation": "none"
                      },
                      {
                        "Automatable": "no"
                      },
                      {
                        "Technical Impact": "partial"
                      }
                    ],
                    "role": "CISA Coordinator",
                    "timestamp": "2025-10-17T17:14:24.314787Z",
                    "version": "2.0.3"
                  },
                  "type": "ssvc"
                }
              }
            ],
            "providerMetadata": {
              "dateUpdated": "2025-10-17T17:14:27.767Z",
              "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
              "shortName": "CISA-ADP"
            },
            "title": "CISA ADP Vulnrichment"
          }
        ],
        "cna": {
          "affected": [
            {
              "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
              "cpes": [
                "cpe:/a:redhat:enterprise_linux:8::appstream",
                "cpe:/a:redhat:enterprise_linux:8::crb"
              ],
              "defaultStatus": "affected",
              "packageName": "virt-devel:rhel",
              "product": "Red Hat Enterprise Linux 8",
              "vendor": "Red Hat",
              "versions": [
                {
                  "lessThan": "*",
                  "status": "unaffected",
                  "version": "8100020240314161907.e155f54d",
                  "versionType": "rpm"
                }
              ]
            },
            {
              "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
              "cpes": [
                "cpe:/a:redhat:enterprise_linux:8::appstream",
                "cpe:/a:redhat:enterprise_linux:8::crb"
              ],
              "defaultStatus": "affected",
              "packageName": "virt:rhel",
              "product": "Red Hat Enterprise Linux 8",
              "vendor": "Red Hat",
              "versions": [
                {
                  "lessThan": "*",
                  "status": "unaffected",
                  "version": "8100020240314161907.e155f54d",
                  "versionType": "rpm"
                }
              ]
            },
            {
              "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
              "cpes": [
                "cpe:/a:redhat:enterprise_linux:9::appstream"
              ],
              "defaultStatus": "affected",
              "packageName": "qemu-kvm",
              "product": "Red Hat Enterprise Linux 9",
              "vendor": "Red Hat",
              "versions": [
                {
                  "lessThan": "*",
                  "status": "unaffected",
                  "version": "17:8.2.0-11.el9_4",
                  "versionType": "rpm"
                }
              ]
            },
            {
              "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
              "cpes": [
                "cpe:/o:redhat:enterprise_linux:6"
              ],
              "defaultStatus": "unaffected",
              "packageName": "qemu-kvm",
              "product": "Red Hat Enterprise Linux 6",
              "vendor": "Red Hat"
            },
            {
              "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
              "cpes": [
                "cpe:/o:redhat:enterprise_linux:7"
              ],
              "defaultStatus": "unaffected",
              "packageName": "qemu-kvm",
              "product": "Red Hat Enterprise Linux 7",
              "vendor": "Red Hat"
            },
            {
              "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
              "cpes": [
                "cpe:/o:redhat:enterprise_linux:7"
              ],
              "defaultStatus": "unaffected",
              "packageName": "qemu-kvm-ma",
              "product": "Red Hat Enterprise Linux 7",
              "vendor": "Red Hat"
            },
            {
              "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
              "cpes": [
                "cpe:/a:redhat:advanced_virtualization:8::el8"
              ],
              "defaultStatus": "unaffected",
              "packageName": "virt:av/qemu-kvm",
              "product": "Red Hat Enterprise Linux 8 Advanced Virtualization",
              "vendor": "Red Hat"
            }
          ],
          "credits": [
            {
              "lang": "en",
              "value": "Red Hat would like to thank Kevin Denis (Synacktiv) for reporting this issue."
            }
          ],
          "datePublic": "2023-07-04T00:00:00.000Z",
          "descriptions": [
            {
              "lang": "en",
              "value": "A flaw was found in the QEMU built-in VNC server while processing ClientCutText messages. A wrong exit condition may lead to an infinite loop when inflating an attacker controlled zlib buffer in the `inflate_buffer` function. This could allow a remote authenticated client who is able to send a clipboard to the VNC server to trigger a denial of service."
            }
          ],
          "metrics": [
            {
              "other": {
                "content": {
                  "namespace": "https://access.redhat.com/security/updates/classification/",
                  "value": "Moderate"
                },
                "type": "Red Hat severity rating"
              }
            },
            {
              "cvssV3_1": {
                "attackComplexity": "LOW",
                "attackVector": "NETWORK",
                "availabilityImpact": "HIGH",
                "baseScore": 6.5,
                "baseSeverity": "MEDIUM",
                "confidentialityImpact": "NONE",
                "integrityImpact": "NONE",
                "privilegesRequired": "LOW",
                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
                "version": "3.1"
              },
              "format": "CVSS"
            }
          ],
          "problemTypes": [
            {
              "descriptions": [
                {
                  "cweId": "CWE-835",
                  "description": "Loop with Unreachable Exit Condition",
                  "lang": "en",
                  "type": "CWE"
                }
              ]
            }
          ],
          "providerMetadata": {
            "dateUpdated": "2026-11-01T03:01:56.984Z",
            "orgId": "53f830b8-0a3f-465b-8143-3b8a9948e749",
            "shortName": "redhat"
          },
          "references": [
            {
              "name": "RHSA-2024:2135",
              "tags": [
                "vendor-advisory",
                "x_refsource_REDHAT"
              ],
              "url": "https://access.redhat.com/errata/RHSA-2024:2135"
            },
            {
              "name": "RHSA-2024:2962",
              "tags": [
                "vendor-advisory",
                "x_refsource_REDHAT"
              ],
              "url": "https://access.redhat.com/errata/RHSA-2024:2962"
            },
            {
              "tags": [
                "vdb-entry",
                "x_refsource_REDHAT"
              ],
              "url": "https://access.redhat.com/security/cve/CVE-2023-3255"
            },
            {
              "name": "RHBZ#2218486",
              "tags": [
                "issue-tracking",
                "x_refsource_REDHAT"
              ],
              "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2218486"
            }
          ],
          "timeline": [
            {
              "lang": "en",
              "time": "2023-06-28T00:00:00.000Z",
              "value": "Reported to Red Hat."
            },
            {
              "lang": "en",
              "time": "2023-07-04T00:00:00.000Z",
              "value": "Made public."
            }
          ],
          "title": "Qemu: vnc: infinite loop in inflate_buffer() leads to denial of service",
          "x_generator": {
            "engine": "cvelib 1.8.0"
          },
          "x_redhatCweChain": "CWE-835: Loop with Unreachable Exit Condition"
        }
      },
      "cveMetadata": {
        "assignerOrgId": "53f830b8-0a3f-465b-8143-3b8a9948e749",
        "assignerShortName": "redhat",
        "cveId": "CVE-2023-3255",
        "datePublished": "2023-09-13T16:12:52.294Z",
        "dateReserved": "2023-06-14T21:08:31.376Z",
        "dateUpdated": "2026-11-01T03:01:56.984Z",
        "state": "PUBLISHED"
      },
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.


Loading…

Loading…

Loading…

Drag nodes to arrange them. Double-click a related vulnerability to open it, or a source to visit its link. The Physics button on the left tunes the layout and the simulation; the legend at the bottom left hides or shows nodes by kind and by sighting type.

Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

JSON
How durations are calculated

Following the VTEM framework (Black Hat USA 2015), time to patch starts when the vendor or a coordinator was informed, total time to patch at discovery, and disclosure to patch at public disclosure; vendor response time runs from the report to its acknowledgement. Time to exploit and time unpatched start at the earliest discovery or report, falling back to public disclosure. Unpatched time ends at the first recorded patch, or the calculation time when no patch is recorded. Exploitation to patch shows the interval between those two events; a published proof of concept is a public exploit, not exploitation.

Each result shows its source dates. A negative interval means the end event came first; when date-only inputs leave the order open, the result says so. Date-only inputs are approximate. The earliest evidence wins: KEV report dates and sightings are labelled as such. Records describing another vulnerability are listed but never calculated from, and a PoC alone does not establish exploitation. Missing patch evidence does not prove that no patch exists. Filters below change the event list only.

Events included in the timeline

Loading timeline…


    Loading…

    Loading…

    Loading…

    Related by attack behaviour

    Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.