{
  "cveId": "CVE-2026-80206",
  "url": "https://patchblox.com/security/cve/CVE-2026-80206",
  "summary": "CVE-2026-80206 is fixed in nltk on 1 platform by DEBIAN-CVE-2026-80206 (version 3.10.3-1), released August 27, 2026. It is not reported as exploited. Patch Radar priority: Routine.",
  "title": "nltk: NLTK before 3.10.3 contains a regular expression denial of service (ReDoS) vulnerability in the tgrep module",
  "description": "NLTK before 3.10.3 contains a regular expression denial of service (ReDoS) vulnerability in the tgrep module. The _tgrep_node_action function compiles user-supplied regular expressions embedded in /regex/ pattern nodes and executes them via re.search against tree node labels without any validation or timeout. An attacker who controls the tgrep pattern (e.g., via tgrep_positions() or tgrep_compile() exposed to external input) can supply a pattern that triggers catastrophic backtracking, causing indefinite CPU saturation that blocks the Python process.",
  "published": "2026-08-26T11:16:40Z",
  "severity": "",
  "epss": 0.0044,
  "epssPercentile": 0.38517,
  "priority": "Routine",
  "priorityTier": 4,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
  "fixes": [
    {
      "platform": "linux",
      "product": "nltk",
      "release": "Debian 14",
      "fixedVersion": "3.10.3-1",
      "fix": "DEBIAN-CVE-2026-80206",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-80206",
      "released": "2026-08-27T00:27:02Z"
    }
  ],
  "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"
  }
}