{
  "cveId": "CVE-2026-44637",
  "url": "https://patchblox.com/security/cve/CVE-2026-44637",
  "summary": "CVE-2026-44637 is fixed in libsixel on 1 platform by DEBIAN-CVE-2026-44637 (version 1:1.8.7-r2-1), released May 27, 2026. It is not reported as exploited. Patch Radar priority: High.",
  "title": "libsixel: libsixel is a SIXEL encoder/decoder implementation derived from kmiya\u0027s sixel",
  "description": "libsixel is a SIXEL encoder/decoder implementation derived from kmiya\u0027s sixel. From  to 1.8.7-r1, a signed integer overflow in the SIXEL parser\u0027s image-buffer doubling loop can lead to an out-of-bounds heap write in sixel_decode_raw_impl. context-\u003Epos_x grows by repeat_count on every sixel character with no upper bound check. Once pos_x approaches INT_MAX, the expression \u0022pos_x \u002B repeat_count\u0022 used to size the image buffer overflows signed int. Depending on how the overflow wraps, the resize check that should reject oversized buffers can be bypassed, after which a subsequent write computes a large attacker-influenced offset into image-\u003Edata and writes past the allocation. Reachable from any caller that decodes attacker-supplied SIXEL data, including img2sixel. This vulnerability is fixed in 1.8.7-r2.",
  "published": "2026-05-14T20:17:08Z",
  "severity": "high",
  "cvss": 7.1,
  "cvssVector": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:H",
  "epss": 0.0016,
  "epssPercentile": 0.05173,
  "priority": "High",
  "priorityTier": 3,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
  "fixes": [
    {
      "platform": "linux",
      "product": "libsixel",
      "release": "Debian 14",
      "fixedVersion": "1:1.8.7-r2-1",
      "fix": "DEBIAN-CVE-2026-44637",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-44637",
      "released": "2026-05-27T17:38:13Z"
    }
  ],
  "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"
  }
}