CVE-2026-81726

NLTK through 3.10.3 contains a path traversal vulnerability in model-artifact APIs that bypass pathsec enforcement by using raw file operations on caller-controlled paths. Attackers can read or write files outside allowed sandbox roots through TransitionParser, AveragedPerceptron, PerceptronTagger, and maxent parameter APIs when pathsec is enabled.

CVSS v3 7.0 HIGH

7.0^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.2 / Impact : 4.7

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact LOW

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/nltk/nltk/security/advisories/GHSA-8mgp-746c-j5xp	Exploit Vendor Advisory
https://www.vulncheck.com/advisories/nltk-through-3.10.3-path-traversal-via-model-artifact-apis	Third Party Advisory
https://github.com/nltk/nltk/security/advisories/GHSA-8mgp-746c-j5xp	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:nltk:nltk:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-08-27 17:21

Updated : 2026-08-31 19:06

NVD link : CVE-2026-81726

Mitre link : CVE-2026-81726

CVE.ORG link : CVE-2026-81726

JSON object : View

Products Affected

nltk

nltk

CWE

CWE-73

External Control of File Name or Path

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