{
  "cveId": "CVE-2026-59679",
  "url": "https://patchblox.com/security/cve/CVE-2026-59679",
  "summary": "CVE-2026-59679 is fixed in 5 products on 1 platform, first by SUSE-SU-2026:3500-1, released August 5, 2026. It is not reported as exploited. Patch Radar priority: High.",
  "title": "fs_read_glyphs() heap OOB read/write via encoding array index mismatch in libXfont2",
  "description": "fs_read_glyphs() in the libXfont2 font-server client (src/fc/fserve.c) indexes the per-character encoding[] array using num_chars from the FS_QueryXBitmaps16 reply, but that array was allocated with a size derived from num_extents in the separate FS_QueryXExtents16 reply. The two CARD32 fields are never cross-checked. A malicious or compromised font server can send a small num_extents (e.g. 1) in the extents reply, then a large num_chars (e.g. 100000) in the bitmaps reply. This causes attacker-controlled out-of-bounds heap read and writes.",
  "published": "2026-08-05T10:00:00Z",
  "severity": "Important",
  "cvss": 9,
  "cvssVector": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H",
  "cwe": "Out-of-bounds Write",
  "epss": 0.00256,
  "epssPercentile": 0.17398,
  "priority": "High",
  "priorityTier": 3,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
  "vendorAdvisory": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-59679",
  "fixes": [
    {
      "platform": "linux",
      "product": "libXfont2",
      "release": "RHEL 10",
      "fixedVersion": "2.0.6-5.el10_0.2",
      "fix": "RHSA-2026:62123",
      "url": "https://patchblox.com/security/fix/linux/rhsa-2026-62123",
      "released": "2026-08-17T23:00:29Z"
    },
    {
      "platform": "linux",
      "product": "libXfont2",
      "release": "RHEL 8",
      "fixedVersion": "0:2.0.3-2.el8_10.3",
      "fix": "RHSA-2026:55446",
      "url": "https://patchblox.com/security/fix/linux/rhsa-2026-55446",
      "released": "2026-08-19T23:17:39Z"
    },
    {
      "platform": "linux",
      "product": "libXfont2",
      "release": "RHEL 9",
      "fixedVersion": "0:2.0.3-12.el9_8.3",
      "fix": "RHSA-2026:55447",
      "url": "https://patchblox.com/security/fix/linux/rhsa-2026-55447",
      "released": "2026-08-19T23:18:54Z"
    },
    {
      "platform": "linux",
      "product": "libXfont2",
      "release": "almalinux 10",
      "fixedVersion": "2.0.6-5.el10_2.3",
      "fix": "ALSA-2026:55448",
      "url": "https://patchblox.com/security/fix/linux/alsa-2026-55448",
      "released": "2026-08-17T00:00:00Z"
    },
    {
      "platform": "linux",
      "product": "libXfont2",
      "release": "almalinux 8",
      "fixedVersion": "2.0.3-2.el8_10.3",
      "fix": "ALSA-2026:55446",
      "url": "https://patchblox.com/security/fix/linux/alsa-2026-55446",
      "released": "2026-08-17T00:00:00Z"
    },
    {
      "platform": "linux",
      "product": "libXfont2",
      "release": "almalinux 9",
      "fixedVersion": "2.0.3-12.el9_8.3",
      "fix": "ALSA-2026:55447",
      "url": "https://patchblox.com/security/fix/linux/alsa-2026-55447",
      "released": "2026-08-17T00:00:00Z"
    },
    {
      "platform": "linux",
      "product": "libXfont2",
      "release": "amzn 2023",
      "fixedVersion": "2.0.7-1.amzn2023.0.3",
      "fix": "ALAS2023-2026-2112",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-2112",
      "released": "2026-08-31T09:00:00Z"
    },
    {
      "platform": "linux",
      "product": "libXfont2",
      "release": "ol 10",
      "fixedVersion": "0:2.0.6-5.el10_2.3",
      "fix": "ELSA-2026-55448",
      "url": "https://patchblox.com/security/fix/linux/elsa-2026-55448",
      "released": "2026-08-17T00:00:00Z"
    },
    {
      "platform": "linux",
      "product": "libXfont2",
      "release": "ol 8",
      "fixedVersion": "0:2.0.3-2.el8_10.3",
      "fix": "ELSA-2026-55446",
      "url": "https://patchblox.com/security/fix/linux/elsa-2026-55446",
      "released": "2026-08-17T00:00:00Z"
    },
    {
      "platform": "linux",
      "product": "libXfont2",
      "release": "ol 9",
      "fixedVersion": "0:2.0.3-12.el9_8.3",
      "fix": "ELSA-2026-55447",
      "url": "https://patchblox.com/security/fix/linux/elsa-2026-55447",
      "released": "2026-08-17T00:00:00Z"
    },
    {
      "platform": "linux",
      "product": "libXfont2",
      "release": "opensuse-leap 16.0",
      "fixedVersion": "2.0.7-160000.5.1",
      "fix": "OPENSUSE-SU-2026:21539-1",
      "url": "https://patchblox.com/security/fix/linux/opensuse-su-2026-21539-1",
      "released": "2026-08-06T09:10:31Z"
    },
    {
      "platform": "linux",
      "product": "libXfont2",
      "release": "rocky 10",
      "fixedVersion": "0:2.0.6-5.el10_2.3",
      "fix": "RLSA-2026:55448",
      "url": "https://patchblox.com/security/fix/linux/rlsa-2026-55448",
      "released": "2026-08-17T18:06:54Z"
    },
    {
      "platform": "linux",
      "product": "libXfont2",
      "release": "rocky 8",
      "fixedVersion": "0:2.0.3-2.el8_10.3",
      "fix": "RLSA-2026:55446",
      "url": "https://patchblox.com/security/fix/linux/rlsa-2026-55446",
      "released": "2026-08-17T18:01:12Z"
    },
    {
      "platform": "linux",
      "product": "libXfont2",
      "release": "rocky 9",
      "fixedVersion": "0:2.0.3-12.el9_8.3",
      "fix": "RLSA-2026:55447",
      "url": "https://patchblox.com/security/fix/linux/rlsa-2026-55447",
      "released": "2026-08-17T18:03:57Z"
    },
    {
      "platform": "linux",
      "product": "libXfont2",
      "release": "sles 15.6",
      "fixedVersion": "2.0.3-150000.3.6.1",
      "fix": "SUSE-SU-2026:3500-1",
      "url": "https://patchblox.com/security/fix/linux/suse-su-2026-3500-1",
      "released": "2026-08-05T11:57:55Z"
    },
    {
      "platform": "linux",
      "product": "libXfont2",
      "release": "sles 15.7",
      "fixedVersion": "2.0.3-150000.3.6.1",
      "fix": "SUSE-SU-2026:3500-1",
      "url": "https://patchblox.com/security/fix/linux/suse-su-2026-3500-1",
      "released": "2026-08-05T11:57:55Z"
    },
    {
      "platform": "linux",
      "product": "libXfont2",
      "release": "sles 16.0",
      "fixedVersion": "2.0.7-160000.5.1",
      "fix": "SUSE-SU-2026:23151-1",
      "url": "https://patchblox.com/security/fix/linux/suse-su-2026-23151-1",
      "released": "2026-08-06T09:11:09Z"
    },
    {
      "platform": "linux",
      "product": "libXfont2-debuginfo",
      "release": "amzn 2023",
      "fixedVersion": "2.0.7-1.amzn2023.0.3",
      "fix": "ALAS2023-2026-2112",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-2112",
      "released": "2026-08-31T09:00:00Z"
    },
    {
      "platform": "linux",
      "product": "libXfont2-debugsource",
      "release": "amzn 2023",
      "fixedVersion": "2.0.7-1.amzn2023.0.3",
      "fix": "ALAS2023-2026-2112",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-2112",
      "released": "2026-08-31T09:00:00Z"
    },
    {
      "platform": "linux",
      "product": "libXfont2-devel",
      "release": "RHEL 8",
      "fixedVersion": "0:2.0.3-2.el8_10.3",
      "fix": "RHSA-2026:55446",
      "url": "https://patchblox.com/security/fix/linux/rhsa-2026-55446",
      "released": "2026-08-19T23:17:39Z"
    },
    {
      "platform": "linux",
      "product": "libXfont2-devel",
      "release": "RHEL 9",
      "fixedVersion": "0:2.0.3-12.el9_8.3",
      "fix": "RHSA-2026:55447",
      "url": "https://patchblox.com/security/fix/linux/rhsa-2026-55447",
      "released": "2026-08-19T23:18:54Z"
    },
    {
      "platform": "linux",
      "product": "libXfont2-devel",
      "release": "almalinux 10",
      "fixedVersion": "2.0.6-5.el10_2.3",
      "fix": "ALSA-2026:55448",
      "url": "https://patchblox.com/security/fix/linux/alsa-2026-55448",
      "released": "2026-08-17T00:00:00Z"
    },
    {
      "platform": "linux",
      "product": "libXfont2-devel",
      "release": "almalinux 8",
      "fixedVersion": "2.0.3-2.el8_10.3",
      "fix": "ALSA-2026:55446",
      "url": "https://patchblox.com/security/fix/linux/alsa-2026-55446",
      "released": "2026-08-17T00:00:00Z"
    },
    {
      "platform": "linux",
      "product": "libXfont2-devel",
      "release": "almalinux 9",
      "fixedVersion": "2.0.3-12.el9_8.3",
      "fix": "ALSA-2026:55447",
      "url": "https://patchblox.com/security/fix/linux/alsa-2026-55447",
      "released": "2026-08-17T00:00:00Z"
    },
    {
      "platform": "linux",
      "product": "libXfont2-devel",
      "release": "amzn 2023",
      "fixedVersion": "2.0.7-1.amzn2023.0.3",
      "fix": "ALAS2023-2026-2112",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-2112",
      "released": "2026-08-31T09:00:00Z"
    },
    {
      "platform": "linux",
      "product": "libXfont2-devel",
      "release": "ol 10",
      "fixedVersion": "0:2.0.6-5.el10_2.3",
      "fix": "ELSA-2026-55448",
      "url": "https://patchblox.com/security/fix/linux/elsa-2026-55448",
      "released": "2026-08-17T00:00:00Z"
    },
    {
      "platform": "linux",
      "product": "libXfont2-devel",
      "release": "ol 8",
      "fixedVersion": "0:2.0.3-2.el8_10.3",
      "fix": "ELSA-2026-55446",
      "url": "https://patchblox.com/security/fix/linux/elsa-2026-55446",
      "released": "2026-08-17T00:00:00Z"
    },
    {
      "platform": "linux",
      "product": "libXfont2-devel",
      "release": "ol 9",
      "fixedVersion": "0:2.0.3-12.el9_8.3",
      "fix": "ELSA-2026-55447",
      "url": "https://patchblox.com/security/fix/linux/elsa-2026-55447",
      "released": "2026-08-17T00:00:00Z"
    },
    {
      "platform": "linux",
      "product": "libxfont",
      "release": "Debian 14",
      "fixedVersion": "1:2.0.9-1",
      "fix": "DEBIAN-CVE-2026-59679",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-59679",
      "released": "2026-08-10T15:53:58Z"
    }
  ],
  "noFixYet": [],
  "dataAsOf": "2026-11-08T13:06:02Z",
  "attribution": {
    "text": "Data: Patchblox Patch Radar",
    "url": "https://patchblox.com/security/patch-radar",
    "terms": "https://patchblox.com/security/patch-radar/use-the-data"
  }
}