GHSA-CV22-G7MW-8V73 NLTK CrubadanCorpusReader path traversal allows arbitrary file disclosure

NLTK 3.9.4 through 3.10.2 contains a path traversal vulnerability in CrubadanCorpusReader. loadlangngrams joins the corpus root with crubadancode, the column-0 value read from the corpus table.txt mapping file, and opens the result with the builtin open rather than the pathsec-validated opener, s...

GHSA-CV2G-M8RR-888C Duplicate Advisory: Natural Language Toolkit (NLTK) has unbounded recursion in JSONTaggedDecoder.decode_obj() may cause DoS

Duplicate Advisory This advisory has been withdrawn because it is a duplicate of GHSA-rf74-v2fm-23pw. This link is maintained to preserve external references. Original Description NLTK versions before 3.9.4 contain an unbounded recursion vulnerability in JSONTaggedDecoder.decodeobj that allows...

Duplicate Advisory: NLTK: Missing Post-Download Integrity Verification Allows Malicious Package Injection

Duplicate Advisory This advisory has been withdrawn because it is a duplicate of GHSA-5wp5-5229-5g6q. This link is maintained to preserve external references. Original Description NLTK before 3.9.3 fails to verify file integrity after downloading packages and before extraction in the downloader...

GHSA-GF32-CMJH-8M9V Duplicate Advisory: NLTK: Missing Post-Download Integrity Verification Allows Malicious Package Injection

Duplicate Advisory This advisory has been withdrawn because it is a duplicate of GHSA-5wp5-5229-5g6q. This link is maintained to preserve external references. Original Description NLTK before 3.9.3 fails to verify file integrity after downloading packages and before extraction in the downloader...

CVE-2026-70626

NLTK versions before 3.9.4 contain a symlink escape vulnerability in CorpusReader.open that allows local attackers to read arbitrary files outside the corpus root. The vulnerability exists because path validation is lexical and does not account for symlink resolution, enabling attackers to place...

CVE-2026-66393

NLTK versions before 3.9.4 contain an unbounded recursion vulnerability in JSONTaggedDecoder.decodeobj that allows attackers to cause denial of service by supplying deeply nested JSON structures. Attackers can craft JSON payloads exceeding the recursion limit to trigger an unhandled RecursionErro...

PYSEC-2026-3729

NLTK before 3.9.3 fails to verify file integrity after downloading packages and before extraction in the downloader module. Attackers can perform man-in-the-middle attacks or DNS poisoning to inject malicious package contents that are extracted without validation...

CVE-2026-63311

NLTK before 3.10.0 affected versions = 3.9.4 contains a server-side request forgery SSRF vulnerability in the validatenetworkurl function in nltk/pathsec.py. The resolvehostname helper catches OSError and ValueError during socket.getaddrinfo and returns an empty list; when DNS resolution fails, t...

CVE-2026-63312

NLTK before 3.10.0 contains an arbitrary local file read vulnerability in StreamBackedCorpusView that bypasses pathsec.ENFORCE by calling builtins.open directly instead of pathsec.open. Attackers who control the fileid argument can read arbitrary local files regardless of the ENFORCE setting,...

CVE-2026-65915

NLTK versions before 3.10.0 contain a logic bug in FileSystemPathPointer.open where the sandbox validation check compares a normalized path against itself, making the security check permanently inert. Attackers can pass file:// URLs to nltk.data.load to read arbitrary files accessible to the...

PYSEC-2026-3729

NLTK before 3.9.3 fails to verify file integrity after downloading packages and before extraction in the downloader module. Attackers can perform man-in-the-middle attacks or DNS poisoning to inject malicious package contents that are extracted without validation...

CVE-2026-63310

Rejected reason: This CVE ID has been rejected or withdrawn by its CVE Numbering Authority...

CVE-2026-62384

NLTK versions before 3.10.2 contain a symlink-based sandbox bypass in FramenetCorpusReader that allows attackers to read arbitrary XML files outside the corpus root. Attackers can place symlinks with names containing no path separators inside the corpus subdirectory, which pass the path validatio...

CVE-2026-62388

NLTK versions before 3.10.0 default to ENFORCE=False in pathsec.py, causing all security validation functions to emit warnings instead of raising exceptions. Attackers can bypass path traversal and pickle deserialization protections by exploiting the disabled security controls that are only activ...

CVE-2026-62385

NLTK versions before 3.10.0 contain a path traversal vulnerability in FramenetCorpusReader and NKJPCorpusReader that allows attackers to parse XML files outside the corpus root by supplying unsafe selectors or poisoned index state. Attackers can exploit framebyname, doc, lu, and header methods wi...

CVE-2026-62383

nltk versions before 3.10.2 contain a symlink-based arbitrary file read vulnerability in IPIPANCorpusReader methods that bypass nltk.pathsec validation entirely. Attackers can place a symlink in the corpus root directory and read arbitrary files accessible to the process by calling channels,...

CVE-2026-66393

NLTK versions before 3.9.4 contain an unbounded recursion vulnerability in JSONTaggedDecoder.decodeobj that allows attackers to cause denial of service by supplying deeply nested JSON structures. Attackers can craft JSON payloads exceeding the recursion limit to trigger an unhandled RecursionErro...

CVE-2026-63311

NLTK before 3.10.0 affected versions = 3.9.4 contains a server-side request forgery SSRF vulnerability in the validatenetworkurl function in nltk/pathsec.py. The resolvehostname helper catches OSError and ValueError during socket.getaddrinfo and returns an empty list; when DNS resolution fails, t...

CVE-2026-62385

NLTK versions before 3.10.0 contain a path traversal vulnerability in FramenetCorpusReader and NKJPCorpusReader that allows attackers to parse XML files outside the corpus root by supplying unsafe selectors or poisoned index state. Attackers can exploit framebyname, doc, lu, and header methods wi...

CVE-2026-65915

NLTK versions before 3.10.0 contain a logic bug in FileSystemPathPointer.open where the sandbox validation check compares a normalized path against itself, making the security check permanently inert. Attackers can pass file:// URLs to nltk.data.load to read arbitrary files accessible to the...