GHSA-FG9W-WFP5-J933 NLTK: BllipParser passes caller-supplied model paths to the bllipparser C extension with no pathsec check, enabling arbitrary read

Summary BllipParser in nltk/parse/bllip.py hands caller-supplied filesystem paths to the native bllipparser C extension without routing them through NLTK's pathsec validation. The constructor parameters parsermodel, rerankerfeatures, and rerankerweights, and the alternative fromunifiedmodeldir...

NLTK: BllipParser passes caller-supplied model paths to the bllipparser C extension with no pathsec check, enabling arbitrary read

Summary BllipParser in nltk/parse/bllip.py hands caller-supplied filesystem paths to the native bllipparser C extension without routing them through NLTK's pathsec validation. The constructor parameters parsermodel, rerankerfeatures, and rerankerweights, and the alternative fromunifiedmodeldir...

CVE-2026-126302

NLTK from 3.9.4 before 3.10.4 contains a symlink following vulnerability in nltk.sem.chat80.sqlquery that bypasses the pathsec data-root sandbox containment check. Attackers who can write into a trusted NLTK data root can plant a symbolic link to read SQLite databases outside the sandbox...

EUVD-2026-125219

NLTK from 3.9.4 before 3.10.4 contains a symlink following vulnerability in nltk.sem.chat80.sqlquery that bypasses the pathsec data-root sandbox containment check. Attackers who can write into a trusted NLTK data root can plant a symbolic link to read SQLite databases outside the sandbox...

CVE-2026-126302

The NLTK library versions 3.9.4 before 3.10.4 is vulnerable to a symlink following flaw in the nltk.sem.chat80.sql_query() function. This vulnerability allows an attacker who has write access to a trusted NLTK data root to plant a symbolic link , effectively bypassing the pathsec data-root sandbo...

NLTK: WekaClassifier passes an unvalidated caller-controlled model path to the weka JVM, bypassing nltk.pathsec containment

Summary WekaClassifier in NLTK passes a caller-controlled model file path to the weka Java VM without any nltk.pathsec validation. WekaClassifier.train puts the caller's modelfilename verbatim into the weka argv "-d", modelfilename, ... weka writes the trained model there, and...

GHSA-J456-XH4H-CPF2 NLTK: WekaClassifier passes an unvalidated caller-controlled model path to the weka JVM, bypassing nltk.pathsec containment

Summary WekaClassifier in NLTK passes a caller-controlled model file path to the weka Java VM without any nltk.pathsec validation. WekaClassifier.train puts the caller's modelfilename verbatim into the weka argv "-d", modelfilename, ... weka writes the trained model there, and...

NLTK: Corpus Reader Sandbox Bypass

Summary NLTK corpus-reader constructors can still reach outside-root file and database reads before the nltk.pathsec sandbox boundary is enforced. The PoC shows the safe path blocked by pathsec.open, then LinThesaurusCorpusReader and PanLexLiteCorpusReader succeeding in the same process. Affected...

GHSA-3GQ4-3J92-5W49 NLTK: Corpus Reader Sandbox Bypass

Summary NLTK corpus-reader constructors can still reach outside-root file and database reads before the nltk.pathsec sandbox boundary is enforced. The PoC shows the safe path blocked by pathsec.open, then LinThesaurusCorpusReader and PanLexLiteCorpusReader succeeding in the same process. Affected...

GHSA-P4RW-RVV2-7XWR NLTK: Corpus readers follow symlinks outside trusted roots despite pathsec enforcement

Summary Several corpus readers still step outside NLTK's symlink-aware trusted-root model. They derive in-root paths from trusted corpus state, convert those paths back into plain strings, and reopen them with built-in open rather than nltk.pathsec.open. Details - Vulnerability type: Path travers...

NLTK: Corpus readers follow symlinks outside trusted roots despite pathsec enforcement

Summary Several corpus readers still step outside NLTK's symlink-aware trusted-root model. They derive in-root paths from trusted corpus state, convert those paths back into plain strings, and reopen them with built-in open rather than nltk.pathsec.open. Details - Vulnerability type: Path travers...

EUVD-2026-65526

NLTK: Corpus readers follow symlinks outside trusted roots despite pathsec enforcement...

GHSA-6WW7-3FRV-CQXH NLTK: pathsec SSRF protection can be bypassed when a proxy is configured

Summary Current NLTK source reopens SSRF in proxied environments. pathsec.urlopen validates the requested hostname locally, but once proxy inheritance is enabled the real fetch is performed by the proxy rather than by the validated direct-connect socket path. Details - Vulnerability type:...

NLTK: pathsec SSRF protection can be bypassed when a proxy is configured

Summary Current NLTK source reopens SSRF in proxied environments. pathsec.urlopen validates the requested hostname locally, but once proxy inheritance is enabled the real fetch is performed by the proxy rather than by the validated direct-connect socket path. Details - Vulnerability type:...

GHSA-3HHW-38PF-PXJ6 NLTK: Symlink-based arbitrary file read in IPIPANCorpusReader, bypasses nltk.pathsec entirely

Summary IPIPANCorpusReader nltk/corpus/reader/ipipan.py exposes public methods, channels, domains, categories, and fileidschannels=..., that accept a caller supplied fileids list and read a file via a completely unprotected builtin open call, with no nltk.pathsec involvement at all. A symlink...

EUVD-2026-64339

NLTK: Symlink-based arbitrary file read in IPIPANCorpusReader, bypasses nltk.pathsec entirely...

EUVD-2026-64333

NLTK: StreamBackedCorpusView Bypasses pathsec.ENFORCE - Arbitrary Local File Read...

NLTK: StreamBackedCorpusView Bypasses pathsec.ENFORCE - Arbitrary Local File Read

Summary Setting nltk.pathsec.ENFORCE = True is documented to sandbox all file access to allowed NLTK data directories and raise PermissionError on unauthorized access. However, StreamBackedCorpusView opens files via builtins.open directly, bypassing pathsec.validatepath entirely. An attacker who...

GHSA-X5PH-MJ9P-RFR8 NLTK: StreamBackedCorpusView Bypasses pathsec.ENFORCE - Arbitrary Local File Read

Summary Setting nltk.pathsec.ENFORCE = True is documented to sandbox all file access to allowed NLTK data directories and raise PermissionError on unauthorized access. However, StreamBackedCorpusView opens files via builtins.open directly, bypassing pathsec.validatepath entirely. An attacker who...

SUSE 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, PerceptronTagge...