EUVD-2026-65524
GHSA-rcw8-9qrw-27m2
Severity by source
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/VA:N/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
Network vector and no privileges reflect web-API exposure of the constructors; S:U because exploitation stays within the process boundary with no scope change to other systems.
Primary rating from Vendor (VulnCheck).
CVSS VectorVendor: VulnCheck
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/VA:N/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
Lifecycle Timeline
3DescriptionCVE.org
NLTK versions before 3.10.3 contain a path sandbox bypass vulnerability in corpus-reader constructors that allows attackers to read files outside the intended data root. Attackers can supply arbitrary corpus root paths to LinThesaurusCorpusReader and PanLexLiteCorpusReader constructors to access filesystem content and SQLite databases outside the pathsec sandbox boundary.
AnalysisAI
Path traversal in NLTK before 3.10.3 exposes arbitrary filesystem content and SQLite databases by bypassing the library's pathsec sandbox boundary. The LinThesaurusCorpusReader and PanLexLiteCorpusReader constructors accept caller-supplied corpus root paths without enforcing the intended data-root restriction, enabling CWE-73 (External Control of File Name or Path) exploitation wherever applications forward user-controlled input to these constructors. …
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Attack ChainAIDerived
Hypothetical attack flow derived from CVE metadata
Vulnerability AssessmentAI
| Exploitation | Exploitation requires that the calling application pass externally controlled input as the corpus root path argument to LinThesaurusCorpusReader or PanLexLiteCorpusReader; NLTK corpus readers that do not accept external root paths, or applications that hardcode the corpus root to a fixed value, are not exploitable via this vulnerability. … Additional conditions and limiting factors are described in the full assessment. |
| Risk Assessment | The CVSS 4.0 score of 8.8 (AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/VA:N) reflects the worst-case scenario: a network-accessible application that exposes the affected constructors to unauthenticated user-supplied input. … Full risk analysis with EPSS, KEV, and SSVC signal comparison available after sign-in. |
| Exploit Scenario | An attacker identifies a web API that accepts a corpus name or root path parameter and forwards it directly to PanLexLiteCorpusReader or LinThesaurusCorpusReader. By supplying a crafted path such as an absolute path to /etc/shadow or a relative traversal sequence targeting application configuration files or credential databases, the attacker causes NLTK to open and return content from outside the intended data directory. … |
| Remediation | The primary fix is to upgrade NLTK to version 3.10.3 or later, which closes the pathsec sandbox bypass in the affected corpus-reader constructors; the vendor advisory at https://github.com/nltk/nltk/security/advisories/GHSA-3gq4-3j92-5w49 confirms this release. … Detailed patch versions, workarounds, and compensating controls in full report. |
Recommended ActionAI
Within 24 hours, audit all systems and applications using NLTK and document current deployed versions. …
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Same weakness CWE-73 – External Control of File Name or Path
View allSame technique Authentication Bypass
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External POC / Exploit Code
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