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oesa-2026-3466
Vulnerability from osv_openeuler
Published
2026-08-20 10:00
Modified
2026-08-20 10:00
Summary
libXfont2 security update
Details

libXfont provides the core of the legacy X11 font system, handling the index files (fonts.dir, fonts.alias, fonts.scale), the various font file formats, and rasterizing them. contains runtime library.

Security Fix(es):

A flaw was found in the libXfont2 font-server client. This heap buffer overflow vulnerability allows a malicious font server to send specially crafted glyph data. The fs_read_glyphs() function fails to properly validate the total size of the incoming data, leading to an overwrite of memory beyond the intended buffer. If the X server runs as a privileged user, this could result in privilege escalation, allowing an attacker to gain higher access. If the X server runs as an unprivileged user, it could lead to a denial of service, causing the system to crash.(CVE-2026-44950)

A flaw was found in the libXfont2 font-server client. A remote attacker, by operating a malicious font server, could exploit an out-of-bounds read/write vulnerability. This occurs because the client incorrectly handles font data, leading to an out-of-bounds memory access. This can lead to privilege escalation if the X server runs with root privileges, or a denial of service (crash) if it runs as an unprivileged user.(CVE-2026-59679)

Severity
7.5 (High)
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
References
To clipboard 

{
  "affected": [
    {
      "ecosystem_specific": {
        "aarch64": [
          "libXfont2-2.0.5-6.oe2203sp4.aarch64.rpm",
          "libXfont2-debuginfo-2.0.5-6.oe2203sp4.aarch64.rpm",
          "libXfont2-debugsource-2.0.5-6.oe2203sp4.aarch64.rpm",
          "libXfont2-devel-2.0.5-6.oe2203sp4.aarch64.rpm"
        ],
        "noarch": [
          "libXfont2-help-2.0.5-6.oe2203sp4.noarch.rpm"
        ],
        "src": [
          "libXfont2-2.0.5-6.oe2203sp4.src.rpm"
        ],
        "x86_64": [
          "libXfont2-2.0.5-6.oe2203sp4.x86_64.rpm",
          "libXfont2-debuginfo-2.0.5-6.oe2203sp4.x86_64.rpm",
          "libXfont2-debugsource-2.0.5-6.oe2203sp4.x86_64.rpm",
          "libXfont2-devel-2.0.5-6.oe2203sp4.x86_64.rpm"
        ]
      },
      "package": {
        "ecosystem": "openEuler:22.03-LTS-SP4",
        "name": "libXfont2",
        "purl": "pkg:rpm/openEuler/libXfont2\u0026distro=openEuler-22.03-LTS-SP4"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.0.5-6.oe2203sp4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "aarch64": [
          "libXfont2-2.0.6-4.oe2403sp1.aarch64.rpm",
          "libXfont2-debuginfo-2.0.6-4.oe2403sp1.aarch64.rpm",
          "libXfont2-debugsource-2.0.6-4.oe2403sp1.aarch64.rpm",
          "libXfont2-devel-2.0.6-4.oe2403sp1.aarch64.rpm"
        ],
        "noarch": [
          "libXfont2-help-2.0.6-4.oe2403sp1.noarch.rpm"
        ],
        "src": [
          "libXfont2-2.0.6-4.oe2403sp1.src.rpm"
        ],
        "x86_64": [
          "libXfont2-2.0.6-4.oe2403sp1.x86_64.rpm",
          "libXfont2-debuginfo-2.0.6-4.oe2403sp1.x86_64.rpm",
          "libXfont2-debugsource-2.0.6-4.oe2403sp1.x86_64.rpm",
          "libXfont2-devel-2.0.6-4.oe2403sp1.x86_64.rpm"
        ]
      },
      "package": {
        "ecosystem": "openEuler:24.03-LTS-SP1",
        "name": "libXfont2",
        "purl": "pkg:rpm/openEuler/libXfont2\u0026distro=openEuler-24.03-LTS-SP1"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.0.6-4.oe2403sp1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "aarch64": [
          "libXfont2-2.0.6-4.oe2403sp3.aarch64.rpm",
          "libXfont2-debuginfo-2.0.6-4.oe2403sp3.aarch64.rpm",
          "libXfont2-debugsource-2.0.6-4.oe2403sp3.aarch64.rpm",
          "libXfont2-devel-2.0.6-4.oe2403sp3.aarch64.rpm"
        ],
        "noarch": [
          "libXfont2-help-2.0.6-4.oe2403sp3.noarch.rpm"
        ],
        "src": [
          "libXfont2-2.0.6-4.oe2403sp3.src.rpm"
        ],
        "x86_64": [
          "libXfont2-2.0.6-4.oe2403sp3.x86_64.rpm",
          "libXfont2-debuginfo-2.0.6-4.oe2403sp3.x86_64.rpm",
          "libXfont2-debugsource-2.0.6-4.oe2403sp3.x86_64.rpm",
          "libXfont2-devel-2.0.6-4.oe2403sp3.x86_64.rpm"
        ]
      },
      "package": {
        "ecosystem": "openEuler:24.03-LTS-SP3",
        "name": "libXfont2",
        "purl": "pkg:rpm/openEuler/libXfont2\u0026distro=openEuler-24.03-LTS-SP3"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.0.6-4.oe2403sp3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "aarch64": [
          "libXfont2-2.0.6-4.oe2403sp4.aarch64.rpm",
          "libXfont2-debuginfo-2.0.6-4.oe2403sp4.aarch64.rpm",
          "libXfont2-debugsource-2.0.6-4.oe2403sp4.aarch64.rpm",
          "libXfont2-devel-2.0.6-4.oe2403sp4.aarch64.rpm"
        ],
        "noarch": [
          "libXfont2-help-2.0.6-4.oe2403sp4.noarch.rpm"
        ],
        "src": [
          "libXfont2-2.0.6-4.oe2403sp4.src.rpm"
        ],
        "x86_64": [
          "libXfont2-2.0.6-4.oe2403sp4.x86_64.rpm",
          "libXfont2-debuginfo-2.0.6-4.oe2403sp4.x86_64.rpm",
          "libXfont2-debugsource-2.0.6-4.oe2403sp4.x86_64.rpm",
          "libXfont2-devel-2.0.6-4.oe2403sp4.x86_64.rpm"
        ]
      },
      "package": {
        "ecosystem": "openEuler:24.03-LTS-SP4",
        "name": "libXfont2",
        "purl": "pkg:rpm/openEuler/libXfont2\u0026distro=openEuler-24.03-LTS-SP4"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.0.6-4.oe2403sp4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "aarch64": [
          "libXfont2-2.0.4-3.oe2003sp4.aarch64.rpm",
          "libXfont2-debuginfo-2.0.4-3.oe2003sp4.aarch64.rpm",
          "libXfont2-debugsource-2.0.4-3.oe2003sp4.aarch64.rpm",
          "libXfont2-devel-2.0.4-3.oe2003sp4.aarch64.rpm"
        ],
        "noarch": [
          "libXfont2-help-2.0.4-3.oe2003sp4.noarch.rpm"
        ],
        "src": [
          "libXfont2-2.0.4-3.oe2003sp4.src.rpm"
        ],
        "x86_64": [
          "libXfont2-2.0.4-3.oe2003sp4.x86_64.rpm",
          "libXfont2-debuginfo-2.0.4-3.oe2003sp4.x86_64.rpm",
          "libXfont2-debugsource-2.0.4-3.oe2003sp4.x86_64.rpm",
          "libXfont2-devel-2.0.4-3.oe2003sp4.x86_64.rpm"
        ]
      },
      "package": {
        "ecosystem": "openEuler:20.03-LTS-SP4",
        "name": "libXfont2",
        "purl": "pkg:rpm/openEuler/libXfont2\u0026distro=openEuler-20.03-LTS-SP4"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.0.4-3.oe2003sp4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "severity": "High"
  },
  "details": "libXfont provides the core of the legacy X11 font system, handling the index files (fonts.dir, fonts.alias, fonts.scale), the various font file formats, and rasterizing them.  contains runtime  library.\r\n\r\nSecurity Fix(es):\n\nA flaw was found in the libXfont2 font-server client. This heap buffer overflow vulnerability allows a malicious font server to send specially crafted glyph data. The fs_read_glyphs() function fails to properly validate the total size of the incoming data, leading to an overwrite of memory beyond the intended buffer. If the X server runs as a privileged user, this could result in privilege escalation, allowing an attacker to gain higher access. If the X server runs as an unprivileged user, it could lead to a denial of service, causing the system to crash.(CVE-2026-44950)\n\nA flaw was found in the libXfont2 font-server client. A remote attacker, by operating a malicious font server, could exploit an out-of-bounds read/write vulnerability. This occurs because the client incorrectly handles font data, leading to an out-of-bounds memory access. This can lead to privilege escalation if the X server runs with root privileges, or a denial of service (crash) if it runs as an unprivileged user.(CVE-2026-59679)",
  "id": "OESA-2026-3466",
  "modified": "2026-08-20T10:00:34Z",
  "published": "2026-08-20T10:00:34Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2026-3466"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-44950"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-59679"
    }
  ],
  "schema_version": "1.7.2",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "libXfont2 security update",
  "upstream": [
    "CVE-2026-44950",
    "CVE-2026-59679"
  ]
}



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