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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
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",
            "binary_version": "2.35-0ubuntu3.14"
          },
          {
            "binary_name": "libc-devtools",
            "binary_version": "2.35-0ubuntu3.14"
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          {
            "binary_name": "libc6",
            "binary_version": "2.35-0ubuntu3.14"
          },
          {
            "binary_name": "libc6-amd64",
            "binary_version": "2.35-0ubuntu3.14"
          },
          {
            "binary_name": "libc6-dev-amd64",
            "binary_version": "2.35-0ubuntu3.14"
          },
          {
            "binary_name": "libc6-dev-i386",
            "binary_version": "2.35-0ubuntu3.14"
          },
          {
            "binary_name": "libc6-dev-s390",
            "binary_version": "2.35-0ubuntu3.14"
          },
          {
            "binary_name": "libc6-dev-x32",
            "binary_version": "2.35-0ubuntu3.14"
          },
          {
            "binary_name": "libc6-i386",
            "binary_version": "2.35-0ubuntu3.14"
          },
          {
            "binary_name": "libc6-prof",
            "binary_version": "2.35-0ubuntu3.14"
          },
          {
            "binary_name": "libc6-s390",
            "binary_version": "2.35-0ubuntu3.14"
          },
          {
            "binary_name": "libc6-x32",
            "binary_version": "2.35-0ubuntu3.14"
          },
          {
            "binary_name": "locales",
            "binary_version": "2.35-0ubuntu3.14"
          },
          {
            "binary_name": "locales-all",
            "binary_version": "2.35-0ubuntu3.14"
          },
          {
            "binary_name": "nscd",
            "binary_version": "2.35-0ubuntu3.14"
          }
        ]
      },
      "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"
        }
      ],
      "versions": [
        "2.34-0ubuntu3",
        "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"
          },
          {
            "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"
      ]
    },
    {
      "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"
          },
          {
            "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",
            "binary_version": "2.43-2ubuntu2.3"
          },
          {
            "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": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "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"
  ]
}



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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

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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.


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