HighFix available
nltk — security advisory
A vulnerability in the `filestring()` function of the `nltk.util` module in nltk version 3.9.2 allows arbitrary file read due to improper validation of input paths. The function directly opens files specified by user input without sanitization, enabling attackers to access sensitive system files by providing absolute paths or traversal paths. This vulnerability can be exploited locally or remotely, particularly in scenarios where the function is used in web APIs or other interfaces that accept user-supplied input.
- Products
- nltk
- Affected versions
- 2.0~b9-0ubuntu4, 2.0~b9-0ubuntu4.1~esm2, 2.0~b9-0ubuntu4.1~esm4, 2.0~b9-0ubuntu4.1~esm5, 3.0.4-1, 3.0.5-1, 3.1-1, 3.1-1ubuntu0.1, 3.1-1ubuntu0.1+esm1, 3.1-1ubuntu0.1+esm2, 3.1-1ubuntu0.1+esm3, 3.10.0-1, 3.10.1-1, 3.10.3-1, 3.2.4-1, 3.2.5-1, 3.2.5-1ubuntu0.1, 3.2.5-1ubuntu0.1+esm1, 3.2.5-1ubuntu0.1+esm2, 3.2.5-1ubuntu0.1+esm3, 3.4.5-1, 3.4.5-2, 3.4.5-2ubuntu0.1~esm1, 3.4.5-2ubuntu0.1~esm2, 3.4.5-2ubuntu0.1~esm3, 3.5-1, 3.6.5-1, 3.6.7-1, 3.7-1, 3.7-1ubuntu0.1~esm1, 3.8.1-1, 3.8.1-1ubuntu0.1~esm1, 3.9.1-2, 3.9.1-2build1, 3.9.2-1, 3.9.2-1ubuntu0.1~esm1, 3.9.3-1
- Fixed versions
- 2.0~b9-0ubuntu4.1~esm6, 3.1-1ubuntu0.1+esm4, 3.2.5-1ubuntu0.1+esm4, 3.4.5-2ubuntu0.1~esm4, 3.7-1ubuntu0.1~esm2, 3.8.1-1ubuntu0.1~esm2, 3.9.2-1ubuntu0.1~esm2
- CVEs
- CVE-2026-0846
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 01:56 UTC · Revision 1
Source evidence
A vulnerability in the `filestring()` function of the `nltk.util` module in nltk version 3.9.2 allows arbitrary file read due to improper validation of input paths. The function directly opens files specified by user input without sanitization, enabling attackers to access sensitive system files by providing absolute paths or traversal paths. This vulnerability can be exploited locally or remotely, particularly in scenarios where the function is used in web APIs or other interfaces that accept user-supplied input.
osv:UBUNTU-CVE-2026-0846
nltk
Fixed versions: 2.0~b9-0ubuntu4.1~esm6
nltk
Fixed versions: 3.1-1ubuntu0.1+esm4
nltk
Fixed versions: 3.2.5-1ubuntu0.1+esm4
nltk
Fixed versions: 3.4.5-2ubuntu0.1~esm4
nltk
Fixed versions: 3.7-1ubuntu0.1~esm2
nltk
Fixed versions: 3.8.1-1ubuntu0.1~esm2
nltk
Fixed versions: Not specified
nltk
Fixed versions: Not specified
nltk
Fixed versions: 3.9.2-1ubuntu0.1~esm2
Complete source record
{
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"url": "https://osv.dev/vulnerability/UBUNTU-CVE-2026-0846",
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"summary": "A vulnerability in the `filestring()` function of the `nltk.util` module in nltk version 3.9.2 allows arbitrary file read due to improper validation of input paths. The function directly opens files specified by user input without sanitization, enabling attackers to access sensitive system files by providing absolute paths or traversal paths. This vulnerability can be exploited locally or remotely, particularly in scenarios where the function is used in web APIs or other interfaces that accept user-supplied input.",
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"modified": "2026-10-17T12:57:52.165814604Z",
"provider": "osv",
"upstream": [
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],
"references": [
"https://ubuntu.com/security/CVE-2026-0846",
"https://www.cve.org/CVERecord?id=CVE-2026-0846",
"https://huntr.com/bounties/007b84f8-418e-4300-99d0-bf504c2f97eb",
"https://github.com/nltk/nltk/pull/3485",
"https://github.com/nltk/nltk/commit/1fc626969f013bba104a40e5e760b9d67b2994ea",
"https://github.com/nltk/nltk/commit/5c46f3dac7e0eb10ee7d9f7be9fe732b0ec0af25",
"https://ubuntu.com/security/notices/USN-8302-1"
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},
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"value": "CVE-2026-0846",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 357696,
"published_at": "2026-03-09T20:16:00+00:00"
}