Bug 2525022 (CVE-2026-81726)

Summary: CVE-2026-81726 nltk: NLTK: Unauthorized file access via path traversal in model-artifact APIs
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: high Docs Contact:
Priority: high    
Version: unspecifiedCC: anpicker, bparees, dschmidt, ebourniv, hasun, jfula, jlanda, jowilson, kshier, nyancey, ometelka, ptisnovs, sbunciak, simaishi, stcannon, syedriko, teagle, xdharmai, yguenane
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in NLTK. This vulnerability, known as path traversal, allows an attacker to bypass security restrictions in the model-artifact APIs. By exploiting this, an attacker can perform unauthorized read or write operations on files outside the intended secure directories. This could lead to sensitive information disclosure or system compromise.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Bug Depends On: 2527236, 2527237    
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Description OSIDB Bzimport 2026-08-27 16:53:30 UTC 
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.