Vulnerability-Lookup

ubuntu-cve-2026-4438

Vulnerability from osv_ubuntu

Published

2026-03-20 20:16

Modified

2026-07-27 18:42

Summary

Details

Calling gethostbyaddr or gethostbyaddr_r with a configured nsswitch.conf that specifies the library's DNS backend in the GNU C library version 2.34 to version 2.43 could result in an invalid DNS hostname being returned to the caller in violation of the DNS specification.

Severity

5.4 (Medium)


                    
                      CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N

N/A (UNKNOWN)


                    
                      medium

References

URL

Type

	https://ubuntu.com/security/CVE-2026-4438	REPORT
	https://www.cve.org/CVERecord?id=CVE-2026-4438	REPORT
	https://www.openwall.com/lists/oss-security/2026/…	REPORT
	https://ubuntu.com/security/notices/USN-8611-1	ADVISORY

JSON

To clipboard

{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "eglibc-source",
            "binary_version": "2.19-0ubuntu6.15+esm4"
          },
          {
            "binary_name": "libc-bin",
            "binary_version": "2.19-0ubuntu6.15+esm4"
          },
          {
            "binary_name": "libc-dev-bin",
            "binary_version": "2.19-0ubuntu6.15+esm4"
          },
          {
            "binary_name": "libc6",
            "binary_version": "2.19-0ubuntu6.15+esm4"
          },
          {
            "binary_name": "libc6-amd64",
            "binary_version": "2.19-0ubuntu6.15+esm4"
          },
          {
            "binary_name": "libc6-armel",
            "binary_version": "2.19-0ubuntu6.15+esm4"
          },
          {
            "binary_name": "libc6-dev-amd64",
            "binary_version": "2.19-0ubuntu6.15+esm4"
          },
          {
            "binary_name": "libc6-dev-armel",
            "binary_version": "2.19-0ubuntu6.15+esm4"
          },
          {
            "binary_name": "libc6-dev-i386",
            "binary_version": "2.19-0ubuntu6.15+esm4"
          },
          {
            "binary_name": "libc6-dev-x32",
            "binary_version": "2.19-0ubuntu6.15+esm4"
          },
          {
            "binary_name": "libc6-i386",
            "binary_version": "2.19-0ubuntu6.15+esm4"
          },
          {
            "binary_name": "libc6-pic",
            "binary_version": "2.19-0ubuntu6.15+esm4"
          },
          {
            "binary_name": "libc6-prof",
            "binary_version": "2.19-0ubuntu6.15+esm4"
          },
          {
            "binary_name": "libc6-x32",
            "binary_version": "2.19-0ubuntu6.15+esm4"
          },
          {
            "binary_name": "multiarch-support",
            "binary_version": "2.19-0ubuntu6.15+esm4"
          },
          {
            "binary_name": "nscd",
            "binary_version": "2.19-0ubuntu6.15+esm4"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:14.04:LTS",
        "name": "eglibc",
        "purl": "pkg:deb/ubuntu/eglibc@2.19-0ubuntu6.15+esm4?arch=source\u0026distro=esm-infra-legacy/trusty"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "2.17-93ubuntu4",
        "2.18-0ubuntu1",
        "2.18-0ubuntu2",
        "2.18-0ubuntu4",
        "2.18-0ubuntu5",
        "2.18-0ubuntu6",
        "2.18-0ubuntu7",
        "2.19-0ubuntu2",
        "2.19-0ubuntu3",
        "2.19-0ubuntu4",
        "2.19-0ubuntu5",
        "2.19-0ubuntu6",
        "2.19-0ubuntu6.1",
        "2.19-0ubuntu6.3",
        "2.19-0ubuntu6.4",
        "2.19-0ubuntu6.5",
        "2.19-0ubuntu6.6",
        "2.19-0ubuntu6.7",
        "2.19-0ubuntu6.8",
        "2.19-0ubuntu6.9",
        "2.19-0ubuntu6.10",
        "2.19-0ubuntu6.11",
        "2.19-0ubuntu6.13",
        "2.19-0ubuntu6.14",
        "2.19-0ubuntu6.15",
        "2.19-0ubuntu6.15+esm1",
        "2.19-0ubuntu6.15+esm2",
        "2.19-0ubuntu6.15+esm3",
        "2.19-0ubuntu6.15+esm4"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "glibc-source",
            "binary_version": "2.39-0ubuntu8.8"
          },
          {
            "binary_name": "libc-bin",
            "binary_version": "2.39-0ubuntu8.8"
          },
          {
            "binary_name": "libc-dev-bin",
            "binary_version": "2.39-0ubuntu8.8"
          },
          {
            "binary_name": "libc-devtools",
            "binary_version": "2.39-0ubuntu8.8"
          },
          {
            "binary_name": "libc6",
            "binary_version": "2.39-0ubuntu8.8"
          },
          {
            "binary_name": "libc6-amd64",
            "binary_version": "2.39-0ubuntu8.8"
          },
          {
            "binary_name": "libc6-dev-amd64",
            "binary_version": "2.39-0ubuntu8.8"
          },
          {
            "binary_name": "libc6-dev-i386",
            "binary_version": "2.39-0ubuntu8.8"
          },
          {
            "binary_name": "libc6-dev-s390",
            "binary_version": "2.39-0ubuntu8.8"
          },
          {
            "binary_name": "libc6-dev-x32",
            "binary_version": "2.39-0ubuntu8.8"
          },
          {
            "binary_name": "libc6-i386",
            "binary_version": "2.39-0ubuntu8.8"
          },
          {
            "binary_name": "libc6-s390",
            "binary_version": "2.39-0ubuntu8.8"
          },
          {
            "binary_name": "libc6-x32",
            "binary_version": "2.39-0ubuntu8.8"
          },
          {
            "binary_name": "locales",
            "binary_version": "2.39-0ubuntu8.8"
          },
          {
            "binary_name": "locales-all",
            "binary_version": "2.39-0ubuntu8.8"
          },
          {
            "binary_name": "nscd",
            "binary_version": "2.39-0ubuntu8.8"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:24.04:LTS",
        "name": "glibc",
        "purl": "pkg:deb/ubuntu/glibc@2.39-0ubuntu8.8?arch=source\u0026distro=noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.39-0ubuntu8.8"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "2.38-1ubuntu6",
        "2.38-3ubuntu1",
        "2.39-0ubuntu1",
        "2.39-0ubuntu2",
        "2.39-0ubuntu6",
        "2.39-0ubuntu8",
        "2.39-0ubuntu8.1",
        "2.39-0ubuntu8.2",
        "2.39-0ubuntu8.3",
        "2.39-0ubuntu8.4",
        "2.39-0ubuntu8.5",
        "2.39-0ubuntu8.6",
        "2.39-0ubuntu8.7"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "glibc-source",
            "binary_version": "2.42-0ubuntu3.1"
          },
          {
            "binary_name": "libc-bin",
            "binary_version": "2.42-0ubuntu3.1"
          },
          {
            "binary_name": "libc-dev-bin",
            "binary_version": "2.42-0ubuntu3.1"
          },
          {
            "binary_name": "libc-devtools",
            "binary_version": "2.42-0ubuntu3.1"
          },
          {
            "binary_name": "libc6",
            "binary_version": "2.42-0ubuntu3.1"
          },
          {
            "binary_name": "libc6-amd64",
            "binary_version": "2.42-0ubuntu3.1"
          },
          {
            "binary_name": "libc6-dev-amd64",
            "binary_version": "2.42-0ubuntu3.1"
          },
          {
            "binary_name": "libc6-dev-i386",
            "binary_version": "2.42-0ubuntu3.1"
          },
          {
            "binary_name": "libc6-dev-x32",
            "binary_version": "2.42-0ubuntu3.1"
          },
          {
            "binary_name": "libc6-i386",
            "binary_version": "2.42-0ubuntu3.1"
          },
          {
            "binary_name": "libc6-x32",
            "binary_version": "2.42-0ubuntu3.1"
          },
          {
            "binary_name": "locales",
            "binary_version": "2.42-0ubuntu3.1"
          },
          {
            "binary_name": "locales-all",
            "binary_version": "2.42-0ubuntu3.1"
          },
          {
            "binary_name": "nscd",
            "binary_version": "2.42-0ubuntu3.1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:25.10",
        "name": "glibc",
        "purl": "pkg:deb/ubuntu/glibc@2.42-0ubuntu3.1?arch=source\u0026distro=questing"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "2.41-6ubuntu1",
        "2.41-6ubuntu2",
        "2.41-9ubuntu1",
        "2.42-0ubuntu1",
        "2.42-0ubuntu3",
        "2.42-0ubuntu3.1"
      ]
    }
  ],
  "aliases": [],
  "details": "Calling gethostbyaddr or gethostbyaddr_r with a configured nsswitch.conf that specifies the library\u0027s DNS backend in the GNU C library version 2.34 to version 2.43 could result in an invalid DNS hostname being returned to the caller in violation of the DNS specification.",
  "id": "UBUNTU-CVE-2026-4438",
  "modified": "2026-07-27T18:42:23Z",
  "published": "2026-03-20T20:16:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-4438"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-4438"
    },
    {
      "type": "REPORT",
      "url": "https://www.openwall.com/lists/oss-security/2026/03/23/2"
    },
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-8611-1"
    }
  ],
  "related": [
    "USN-8611-1"
  ],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2026-4438"
  ]
}

CVE-2026-4438 (GCVE-0-2026-4438)

Vulnerability from cvelistv5 – Published: 2026-03-20 19:59 – Updated: 2026-07-14 12:45

Title

gethostbyaddr and gethostbyaddr_r return invalid DNS hostnames

Summary

Severity

5.4 (Medium)


                        
                          CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-03-23 15:06 UTC

CWE

CWE-20 - Improper input validation
CWE-88 - Improper Neutralization of Argument Delimiters in a Command ('Argument Injection')

Assigner

glibc redhat root

References

2 references

URL	Tags
https://sourceware.org/bugzilla/show_bug.cgi?id=34015
https://cert-portal.siemens.com/productcert/html/…

Impacted products

4 products

Vendor	Product	Version
The GNU C Library	glibc	Affected: 2.34 , ≤ 2.43 (custom)
Siemens	SIMATIC S7-1500 CPU 1518-4 PN/DP MFP	Affected: V3.1.5 , < V3.1.6 (custom)
Siemens	SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP	Affected: V3.1.5 , < V3.1.6 (custom)
Siemens	SIPLUS S7-1500 CPU 1518-4 PN/DP MFP	Affected: V3.1.5 , < V3.1.6 (custom)

Date Public

2026-03-20 22:17

Credits

Antonio Maini (0rbitingZer0) - 0rbitingZer0@proton.me

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "cvssV3_1": {
              "attackComplexity": "LOW",
              "attackVector": "ADJACENT_NETWORK",
              "availabilityImpact": "NONE",
              "baseScore": 5.4,
              "baseSeverity": "MEDIUM",
              "confidentialityImpact": "LOW",
              "integrityImpact": "LOW",
              "privilegesRequired": "NONE",
              "scope": "UNCHANGED",
              "userInteraction": "NONE",
              "vectorString": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N",
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                "role": "CISA Coordinator",
                "timestamp": "2026-03-23T15:06:13.636418Z",
                "version": "2.0.3"
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              "type": "ssvc"
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        ],
        "problemTypes": [
          {
            "descriptions": [
              {
                "cweId": "CWE-88",
                "description": "CWE-88 Improper Neutralization of Argument Delimiters in a Command (\u0027Argument Injection\u0027)",
                "lang": "en",
                "type": "CWE"
              }
            ]
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-03-23T15:06:16.376Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
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            "versions": [
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                "version": "V3.1.5",
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        ],
        "providerMetadata": {
          "dateUpdated": "2026-07-14T12:45:26.864Z",
          "orgId": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e",
          "shortName": "siemens-SADP"
        },
        "references": [
          {
            "url": "https://cert-portal.siemens.com/productcert/html/ssa-082556.html"
          }
        ],
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          "type": "finder",
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      "impacts": [
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              "description": "CWE-20 Improper input validation",
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          "url": "https://sourceware.org/bugzilla/show_bug.cgi?id=34015"
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}

usn-8611-1

Vulnerability from osv_ubuntu

Published

2026-07-27 12:24

Modified

2026-07-27 12:24

Summary

glibc vulnerabilities

Details

It was discovered that the GNU C Library iconv function incorrectly handled certain IBM character sets. An attacker could possibly use this issue to cause a denial of service. (CVE-2026-4046)

It was discovered that the GNU C Library DNS functions incorrectly handled certain DNS server responses when using gethostbyaddr or gethostbyaddr_r. An attacker in a privileged network position could possibly use this issue to cause an application to violate DNS specification or obtain incorrect hostname information. This issue only affected Ubuntu 24.04 LTS. (CVE-2026-4437, CVE-2026-4438)

It was discovered that the GNU C Library deprecated debugging functions incorrectly enforced caller-supplied buffer lengths. An attacker could possibly use this issue to cause a denial of service or execute arbitrary code. (CVE-2026-5435)

It was discovered that the GNU C Library scanf family of functions contained a heap buffer overflow when processing certain format specifiers. An attacker could possibly use this issue to cause a denial of service or execute arbitrary code. (CVE-2026-5450)

It was discovered that the GNU C Library ungetwc function incorrectly handled certain character encodings. An attacker could possibly use this issue to obtain sensitive information or cause a denial of service. (CVE-2026-5928)

It was discovered that the GNU C Library deprecated debugging functions incorrectly validated DNS response record data. An attacker could possibly use this issue to cause a denial of service or obtain sensitive information. (CVE-2026-6238)

References

URL

Type

	https://ubuntu.com/security/notices/USN-8611-1	ADVISORY
	https://ubuntu.com/security/CVE-2026-4046	REPORT
	https://ubuntu.com/security/CVE-2026-4437	REPORT
	https://ubuntu.com/security/CVE-2026-4438	REPORT
	https://ubuntu.com/security/CVE-2026-5435	REPORT
	https://ubuntu.com/security/CVE-2026-5450	REPORT
	https://ubuntu.com/security/CVE-2026-5928	REPORT
	https://ubuntu.com/security/CVE-2026-6238	REPORT

JSON

To clipboard

{
  "affected": [
    {
      "database_specific": {
        "cves_map": {
          "cves": [
            {
              "id": "CVE-2026-4046",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2026-5435",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2026-5450",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2026-5928",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2026-6238",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            }
          ],
          "ecosystem": "Ubuntu:22.04:LTS"
        }
      },
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "glibc-source",
            "binary_version": "2.35-0ubuntu3.14"
          },
          {
            "binary_name": "libc-bin",
            "binary_version": "2.35-0ubuntu3.14"
          },
          {
            "binary_name": "libc-dev-bin",
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          },
          {
            "binary_name": "libc-devtools",
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          },
          {
            "binary_name": "libc6",
            "binary_version": "2.35-0ubuntu3.14"
          },
          {
            "binary_name": "libc6-amd64",
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          },
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            "binary_name": "libc6-dev-s390",
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            "binary_name": "libc6-dev-x32",
            "binary_version": "2.35-0ubuntu3.14"
          },
          {
            "binary_name": "libc6-i386",
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          },
          {
            "binary_name": "libc6-prof",
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            "binary_name": "libc6-s390",
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          {
            "binary_name": "libc6-x32",
            "binary_version": "2.35-0ubuntu3.14"
          },
          {
            "binary_name": "locales",
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          },
          {
            "binary_name": "locales-all",
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          },
          {
            "binary_name": "nscd",
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          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:22.04:LTS",
        "name": "glibc",
        "purl": "pkg:deb/ubuntu/glibc@2.35-0ubuntu3.14?arch=source\u0026distro=jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.35-0ubuntu3.14"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
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        "2.35-0ubuntu1",
        "2.35-0ubuntu3",
        "2.35-0ubuntu3.1",
        "2.35-0ubuntu3.3",
        "2.35-0ubuntu3.4",
        "2.35-0ubuntu3.5",
        "2.35-0ubuntu3.6",
        "2.35-0ubuntu3.7",
        "2.35-0ubuntu3.8",
        "2.35-0ubuntu3.9",
        "2.35-0ubuntu3.10",
        "2.35-0ubuntu3.11",
        "2.35-0ubuntu3.12",
        "2.35-0ubuntu3.13"
      ]
    },
    {
      "database_specific": {
        "cves_map": {
          "cves": [
            {
              "id": "CVE-2026-4046",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2026-4437",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2026-4438",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2026-5435",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2026-5450",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2026-5928",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2026-6238",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            }
          ],
          "ecosystem": "Ubuntu:24.04:LTS"
        }
      },
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "glibc-source",
            "binary_version": "2.39-0ubuntu8.8"
          },
          {
            "binary_name": "libc-bin",
            "binary_version": "2.39-0ubuntu8.8"
          },
          {
            "binary_name": "libc-dev-bin",
            "binary_version": "2.39-0ubuntu8.8"
          },
          {
            "binary_name": "libc-devtools",
            "binary_version": "2.39-0ubuntu8.8"
          },
          {
            "binary_name": "libc6",
            "binary_version": "2.39-0ubuntu8.8"
          },
          {
            "binary_name": "libc6-amd64",
            "binary_version": "2.39-0ubuntu8.8"
          },
          {
            "binary_name": "libc6-dev-amd64",
            "binary_version": "2.39-0ubuntu8.8"
          },
          {
            "binary_name": "libc6-dev-i386",
            "binary_version": "2.39-0ubuntu8.8"
          },
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            "binary_name": "libc6-dev-s390",
            "binary_version": "2.39-0ubuntu8.8"
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          {
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            "binary_version": "2.39-0ubuntu8.8"
          },
          {
            "binary_name": "libc6-i386",
            "binary_version": "2.39-0ubuntu8.8"
          },
          {
            "binary_name": "libc6-s390",
            "binary_version": "2.39-0ubuntu8.8"
          },
          {
            "binary_name": "libc6-x32",
            "binary_version": "2.39-0ubuntu8.8"
          },
          {
            "binary_name": "locales",
            "binary_version": "2.39-0ubuntu8.8"
          },
          {
            "binary_name": "locales-all",
            "binary_version": "2.39-0ubuntu8.8"
          },
          {
            "binary_name": "nscd",
            "binary_version": "2.39-0ubuntu8.8"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:24.04:LTS",
        "name": "glibc",
        "purl": "pkg:deb/ubuntu/glibc@2.39-0ubuntu8.8?arch=source\u0026distro=noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.39-0ubuntu8.8"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "2.38-1ubuntu6",
        "2.38-3ubuntu1",
        "2.39-0ubuntu1",
        "2.39-0ubuntu2",
        "2.39-0ubuntu6",
        "2.39-0ubuntu8",
        "2.39-0ubuntu8.1",
        "2.39-0ubuntu8.2",
        "2.39-0ubuntu8.3",
        "2.39-0ubuntu8.4",
        "2.39-0ubuntu8.5",
        "2.39-0ubuntu8.6",
        "2.39-0ubuntu8.7"
      ]
    },
    {
      "database_specific": {
        "cves_map": {
          "cves": [
            {
              "id": "CVE-2026-4046",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2026-5435",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2026-5450",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2026-5928",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2026-6238",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            }
          ],
          "ecosystem": "Ubuntu:26.04:LTS"
        }
      },
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "glibc-source",
            "binary_version": "2.43-2ubuntu2.3"
          },
          {
            "binary_name": "libc-bin",
            "binary_version": "2.43-2ubuntu2.3"
          },
          {
            "binary_name": "libc-dev-bin",
            "binary_version": "2.43-2ubuntu2.3"
          },
          {
            "binary_name": "libc-devtools",
            "binary_version": "2.43-2ubuntu2.3"
          },
          {
            "binary_name": "libc-gconv-modules-extra",
            "binary_version": "2.43-2ubuntu2.3"
          },
          {
            "binary_name": "libc6",
            "binary_version": "2.43-2ubuntu2.3"
          },
          {
            "binary_name": "libc6-amd64",
            "binary_version": "2.43-2ubuntu2.3"
          },
          {
            "binary_name": "libc6-dev-amd64",
            "binary_version": "2.43-2ubuntu2.3"
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          {
            "binary_name": "libc6-dev-i386",
            "binary_version": "2.43-2ubuntu2.3"
          },
          {
            "binary_name": "libc6-dev-x32",
            "binary_version": "2.43-2ubuntu2.3"
          },
          {
            "binary_name": "libc6-i386",
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          },
          {
            "binary_name": "libc6-x32",
            "binary_version": "2.43-2ubuntu2.3"
          },
          {
            "binary_name": "locales",
            "binary_version": "2.43-2ubuntu2.3"
          },
          {
            "binary_name": "locales-all",
            "binary_version": "2.43-2ubuntu2.3"
          },
          {
            "binary_name": "nscd",
            "binary_version": "2.43-2ubuntu2.3"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "glibc",
        "purl": "pkg:deb/ubuntu/glibc@2.43-2ubuntu2.3?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
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            {
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            },
            {
              "fixed": "2.43-2ubuntu2.3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "2.42-0ubuntu3",
        "2.42-2ubuntu1",
        "2.42-2ubuntu2",
        "2.42-2ubuntu4",
        "2.42-2ubuntu5",
        "2.43-2ubuntu1",
        "2.43-2ubuntu2"
      ]
    }
  ],
  "aliases": [],
  "details": "It was discovered that the GNU C Library iconv function incorrectly handled\ncertain IBM character sets. An attacker could possibly use this issue to\ncause a denial of service. (CVE-2026-4046)\n\nIt was discovered that the GNU C Library DNS functions incorrectly handled\ncertain DNS server responses when using gethostbyaddr or gethostbyaddr_r.\nAn attacker in a privileged network position could possibly use this issue\nto cause an application to violate DNS specification or obtain incorrect\nhostname information. This issue only affected Ubuntu 24.04 LTS.\n(CVE-2026-4437, CVE-2026-4438)\n\nIt was discovered that the GNU C Library deprecated debugging functions\nincorrectly enforced caller-supplied buffer lengths. An attacker could\npossibly use this issue to cause a denial of service or execute arbitrary\ncode. (CVE-2026-5435)\n\nIt was discovered that the GNU C Library scanf family of functions\ncontained a heap buffer overflow when processing certain format specifiers.\nAn attacker could possibly use this issue to cause a denial of service or\nexecute arbitrary code. (CVE-2026-5450)\n\nIt was discovered that the GNU C Library ungetwc function incorrectly\nhandled certain character encodings. An attacker could possibly use this\nissue to obtain sensitive information or cause a denial of service.\n(CVE-2026-5928)\n\nIt was discovered that the GNU C Library deprecated debugging functions\nincorrectly validated DNS response record data. An attacker could possibly\nuse this issue to cause a denial of service or obtain sensitive\ninformation. (CVE-2026-6238)",
  "id": "USN-8611-1",
  "modified": "2026-07-27T12:24:25Z",
  "published": "2026-07-27T12:24:25Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-8611-1"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-4046"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-4437"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-4438"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-5435"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-5450"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-5928"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-6238"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "summary": "glibc vulnerabilities",
  "upstream": [
    "UBUNTU-CVE-2026-4046",
    "UBUNTU-CVE-2026-4437",
    "UBUNTU-CVE-2026-4438",
    "UBUNTU-CVE-2026-5435",
    "UBUNTU-CVE-2026-5450",
    "UBUNTU-CVE-2026-5928",
    "UBUNTU-CVE-2026-6238"
  ]
}

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.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

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.

Action not permitted

ubuntu-cve-2026-4438

Vulnerability from osv_ubuntu

CVE-2026-4438 (GCVE-0-2026-4438)

usn-8611-1

Vulnerability from osv_ubuntu

Tags

Sightings

Nomenclature

Related by attack behaviour