{
  "cveId": "CVE-2026-33018",
  "url": "https://patchblox.com/security/cve/CVE-2026-33018",
  "summary": "CVE-2026-33018 is fixed in libsixel on 1 platform by DEBIAN-CVE-2026-33018 (version 1:1.8.7-r2-1), released April 14, 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. Versions 1.8.7 and prior contain a Use-After-Free vulnerability via the load_gif() function in fromgif.c, where a single sixel_frame_t object is reused across all frames of an animated GIF and gif_init_frame() unconditionally frees and reallocates frame-\u003Epixels between frames without consulting the object\u0027s reference count. Because the public API explicitly provides sixel_frame_ref() to retain a frame and sixel_frame_get_pixels() to access the raw pixel buffer, a callback following this documented usage pattern will hold a dangling pointer after the second frame is decoded, resulting in a heap use-after-free confirmed by ASAN. Any application using sixel_helper_load_image_file() with a multi-frame callback to process user-supplied animated GIFs is affected, with a reliable crash as the minimum impact and potential for code execution. This issue has been fixed in version 1.8.7-r1.",
  "published": "2026-04-14T22:16:30Z",
  "severity": "high",
  "cvss": 7,
  "cvssVector": "CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H",
  "epss": 0.00191,
  "epssPercentile": 0.08829,
  "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-2026-33018",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-33018",
      "released": "2026-04-14T22:16:30Z"
    }
  ],
  "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"
  }
}