CVE
CVE-2026-79657
NLTK before 3.10.3 Remote Code Execution via Unsafe Pickle Deserialization
NLTK versions before 3.10.3 contain a remote code execution vulnerability in allowlisted pickle loaders that trust entire module namespaces instead of specific safe callables. Attackers can craft malicious pickle payloads invoking dangerous in-namespace functions like ReppTokenizer._execute and numpy.f2py.crackfortran.myeval through pickle REDUCE to execute arbitrary commands during model or tokenizer artifact loading.
Package Versions Affected
Package Version
patch Availability
No items found.
Automatically patch vulnerabilities without upgrading
Fix Without Upgrading
Detect compatible fix
Apply safe remediation
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CVSS Version
Severity
Base Score
CVSS Version
Score Vector
C
H
U
9.3
-
4.0
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
C
H
U
0
-
C
H
U
-
Related Resources
No items found.
References
https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/79xxx/CVE-2026-79657.json, https://github.com/nltk/nltk/security/advisories/GHSA-x99w-6fgc-pmfw, https://nvd.nist.gov/vuln/detail/CVE-2026-79657, https://www.vulncheck.com/advisories/nltk-before-3.10.3-remote-code-execution-via-unsafe-pickle-deserialization