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ubuntu-cve-2023-3255
Vulnerability from osv_ubuntu
Published
2023-09-13 17:15
Modified
2025-09-08 16:55
Summary
Details

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.

Severity
6.5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
6.5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
N/A (UNKNOWN)
low
References
To clipboard 

{
  "affected": [
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "qemu",
            "binary_version": "1:6.2+dfsg-2ubuntu6.16"
          },
          {
            "binary_name": "qemu-block-extra",
            "binary_version": "1:6.2+dfsg-2ubuntu6.16"
          },
          {
            "binary_name": "qemu-guest-agent",
            "binary_version": "1:6.2+dfsg-2ubuntu6.16"
          },
          {
            "binary_name": "qemu-system",
            "binary_version": "1:6.2+dfsg-2ubuntu6.16"
          },
          {
            "binary_name": "qemu-system-arm",
            "binary_version": "1:6.2+dfsg-2ubuntu6.16"
          },
          {
            "binary_name": "qemu-system-common",
            "binary_version": "1:6.2+dfsg-2ubuntu6.16"
          },
          {
            "binary_name": "qemu-system-data",
            "binary_version": "1:6.2+dfsg-2ubuntu6.16"
          },
          {
            "binary_name": "qemu-system-gui",
            "binary_version": "1:6.2+dfsg-2ubuntu6.16"
          },
          {
            "binary_name": "qemu-system-mips",
            "binary_version": "1:6.2+dfsg-2ubuntu6.16"
          },
          {
            "binary_name": "qemu-system-misc",
            "binary_version": "1:6.2+dfsg-2ubuntu6.16"
          },
          {
            "binary_name": "qemu-system-ppc",
            "binary_version": "1:6.2+dfsg-2ubuntu6.16"
          },
          {
            "binary_name": "qemu-system-s390x",
            "binary_version": "1:6.2+dfsg-2ubuntu6.16"
          },
          {
            "binary_name": "qemu-system-sparc",
            "binary_version": "1:6.2+dfsg-2ubuntu6.16"
          },
          {
            "binary_name": "qemu-system-x86",
            "binary_version": "1:6.2+dfsg-2ubuntu6.16"
          },
          {
            "binary_name": "qemu-system-x86-microvm",
            "binary_version": "1:6.2+dfsg-2ubuntu6.16"
          },
          {
            "binary_name": "qemu-system-x86-xen",
            "binary_version": "1:6.2+dfsg-2ubuntu6.16"
          },
          {
            "binary_name": "qemu-user",
            "binary_version": "1:6.2+dfsg-2ubuntu6.16"
          },
          {
            "binary_name": "qemu-user-binfmt",
            "binary_version": "1:6.2+dfsg-2ubuntu6.16"
          },
          {
            "binary_name": "qemu-user-static",
            "binary_version": "1:6.2+dfsg-2ubuntu6.16"
          },
          {
            "binary_name": "qemu-utils",
            "binary_version": "1:6.2+dfsg-2ubuntu6.16"
          }
        ],
        "priority_reason": "This can only be used as a DoS by an authenticated user to the VNC service."
      },
      "package": {
        "ecosystem": "Ubuntu:22.04:LTS",
        "name": "qemu",
        "purl": "pkg:deb/ubuntu/qemu@1:6.2+dfsg-2ubuntu6.16?arch=source\u0026distro=jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1:6.2+dfsg-2ubuntu6.16"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1:6.0+dfsg-2expubuntu1",
        "1:6.0+dfsg-2expubuntu2",
        "1:6.0+dfsg-2expubuntu4",
        "1:6.2+dfsg-2ubuntu5",
        "1:6.2+dfsg-2ubuntu6",
        "1:6.2+dfsg-2ubuntu6.1",
        "1:6.2+dfsg-2ubuntu6.2",
        "1:6.2+dfsg-2ubuntu6.3",
        "1:6.2+dfsg-2ubuntu6.4",
        "1:6.2+dfsg-2ubuntu6.5",
        "1:6.2+dfsg-2ubuntu6.6",
        "1:6.2+dfsg-2ubuntu6.7",
        "1:6.2+dfsg-2ubuntu6.8",
        "1:6.2+dfsg-2ubuntu6.9",
        "1:6.2+dfsg-2ubuntu6.10",
        "1:6.2+dfsg-2ubuntu6.11",
        "1:6.2+dfsg-2ubuntu6.12",
        "1:6.2+dfsg-2ubuntu6.13",
        "1:6.2+dfsg-2ubuntu6.14",
        "1:6.2+dfsg-2ubuntu6.15"
      ]
    }
  ],
  "aliases": [],
  "details": "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.",
  "id": "UBUNTU-CVE-2023-3255",
  "modified": "2025-09-08T16:55:46Z",
  "published": "2023-09-13T17:15:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2023-3255"
    },
    {
      "type": "REPORT",
      "url": "https://lists.nongnu.org/archive/html/qemu-devel/2023-07/msg00596.html"
    },
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-6567-1"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2023-3255"
    }
  ],
  "related": [
    "USN-6567-1"
  ],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "low",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2023-3255"
  ]
}



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