HighFix available
nltk — security advisory
NLTK before 3.10.3 contains a remote code execution vulnerability in AllowlistUnpickler that validates only the pickle module string and not the global name, allowing attackers to resolve dotted names by attribute traversal to callables outside the allowlisted namespace. Attackers can craft untrusted transition-parser models that execute arbitrary commands when TransitionParser.parse loads the model through allowlisted_pickle_load.
- Products
- nltk
- Affected versions
- 3.10.0-1, 3.10.1-1, 3.10.3-1, 3.8-1, 3.8.1-1, 3.9.1-1, 3.9.1-2, 3.9.2-1, 3.9.3-1
- Fixed versions
- 3.10.3-1
- CVEs
- CVE-2026-71513
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 30 Oct 2026, 16:22 UTC · Revision 1
Source evidence
NLTK before 3.10.3 contains a remote code execution vulnerability in AllowlistUnpickler that validates only the pickle module string and not the global name, allowing attackers to resolve dotted names by attribute traversal to callables outside the allowlisted namespace. Attackers can craft untrusted transition-parser models that execute arbitrary commands when TransitionParser.parse loads the model through allowlisted_pickle_load.
osv:DEBIAN-CVE-2026-71513
nltk
Fixed versions: Not specified
nltk
Fixed versions: Not specified
nltk
Fixed versions: 3.10.3-1
Complete source record
{
"id": "a77ca9aec6e81b9eb403ab7960332560c77814e5eb093457b780d92ab81e475b",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2026-71513",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2026-71513",
"summary": "NLTK before 3.10.3 contains a remote code execution vulnerability in AllowlistUnpickler that validates only the pickle module string and not the global name, allowing attackers to resolve dotted names by attribute traversal to callables outside the allowlisted namespace. Attackers can craft untrusted transition-parser models that execute arbitrary commands when TransitionParser.parse loads the model through allowlisted_pickle_load.",
"evidence": "osv:DEBIAN-CVE-2026-71513",
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"severity": "high",
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"database_specific": {
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}
],
"modified": "2026-10-15T09:47:31.056151957Z",
"provider": "osv",
"upstream": [
"CVE-2026-71513"
],
"references": [
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]
},
"related_cves": [
{
"value": "CVE-2026-71513",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 327578,
"published_at": "2026-08-22T14:16:33.417+00:00"
}