CVE-2026-79674: NLTK · Corpus Reader Sandbox Bypass
Affects gptlineSource GCVE Database
Not known to be exploited · CVSS 8.8 High : upgrade to 1.0.8_23 soon.
Data as of 1 Nov 2026, 22:58 UTC
- EPSS
- 0.3% chance of exploitation in 30 days – higher than 32% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 1.0.8_23
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 2 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 1 Nov 2026.
What to do
Upgrade gptline to 1.0.8_23.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Homebrewgptlinepkg:brew/gptlineOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
A patch is available for this vulnerability. Users should update NLTK to a fixed version where CorpusReader constructors enforce pathsec sandbox validation on the root path and avoid direct builtin open() or sqlite3.connect() calls on unvalidated paths. Until patched, avoid using LinThesaurusCorpusReader and PanLexLiteCorpusReader with untrusted root paths.
Description
NLTK's corpus-reader constructors, specifically LinThesaurusCorpusReader and PanLexLiteCorpusReader, can bypass the nltk.pathsec sandbox designed to restrict file and database access. This allows these readers to perform file and database reads outside the intended sandbox root even when sandbox enforcement is enabled. The vulnerability arises because the CorpusReader.__init__ method converts the root path to a FileSystemPathPointer without applying pathsec validation, and subsequent file/database operations use builtin open() or sqlite3.connect() directly, bypassing sandbox controls.
References
- github.com/nltk/nltk/security/advisories/GHSA-3gq4-3j92-5w49 (opens in a new tab)
- nvd.nist.gov/vuln/detail/CVE-2026-79674 (opens in a new tab)
- github.com/nltk/nltk/commit/bc007200d123c1a98d74c2eb230f5e06c53886b8 (opens in a new tab)
- github.com/nltk/nltk (opens in a new tab)
- github.com/nltk/nltk/releases/tag/v3.10.3 (opens in a new tab)
- github.com/pypa/advisory-database/tree/main/vulns/nltk/PYSEC-2026-3736.yaml (opens in a new tab)
- vulncheck.com/advisories/nltk-path-traversal-via-corpus-reader-constructors (opens in a new tab)