CVEvulnerability
CVE-2026-71513
8.7 HIGH
Official page ↗
- Status
- Analyzed
- Published
- 2026-08-22
- Last modified
- 2026-10-14
- Assigner
- [email protected]
- CVSS 4.0 ([email protected])
- 8.7 HIGH — CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/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
- CVSS 3.1 ([email protected])
- 8.8 HIGH — CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
- Weaknesses
- CWE-502
Description
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.
Affected configurations
• nltk nltk (< 3.10.3)
Related
Weakness · CWE (1)
- CWE-502 Deserialization of Untrusted Data weakness
References
- https://github.com/nltk/nltk Product
- https://github.com/nltk/nltk/blob/v3.10.2/nltk/picklesec.py#L119-L124 Product
- https://github.com/nltk/nltk/commit/c3e37113742a1ebeeb4f2ca58941f320f98805ea Patch
- https://www.vulncheck.com/advisories/nltk-through-remote-code-execution-via-allowlistunpickler-dotted-name-bypass Third Party Advisory, Patch