CVE-2026-63312 NLTK StreamBackedCorpusView Bypasses pathsec.ENFORCE Arbitrary File Read

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-2026-63312

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-2026-63311 NLTK before 3.10.0 SSRF via DNS Resolution Failure

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-2026-63311

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-2026-63311 NLTK before 3.10.0 SSRF via DNS Resolution Failure

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 StreamBackedCorpusView Bypasses pathsec.ENFORCE Arbitrary File Read

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-2026-63311

NLTK (Python NLP library) versions

CVE-2026-63312 NLTK StreamBackedCorpusView Bypasses pathsec.ENFORCE Arbitrary File Read

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,...

EUVD-2026-64335

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

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CVE-2026-63310

CVE-2026-63310 (now rejected by its CNA) tracks a vulnerability in NLTK before 3.9.3 where the package downloader in nltk/downloader.py performs no integrity verification between moving a downloaded file to its final location and extracting it. The SHA-256 checksum logic exists in _pkg_status() b...

CVE-2026-63310

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CVE-2026-63310 NLTK before 3.9.3 Missing Post-Download Integrity Verification

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

Removed by vendor...

CVE-2026-62388 NLTK before 3.10.0 Insecure Default Configuration in pathsec.py

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-2026-62388 NLTK before 3.10.0 Insecure Default Configuration in pathsec.py

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-2026-62388

NLTK (Python Natural Language Processing toolkit) versions before 3.10.0 ship with an insecure default in pathsec.py : the ENFORCE flag is set to False, causing all security validation functions to emit warnings rather than raising exceptions. This means path traversal and pickle deserialization ...

CVE-2026-62388 NLTK before 3.10.0 Insecure Default Configuration in pathsec.py

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-2026-62388

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 3.9.4 Path Traversal via FrameNet and NKJP Readers

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...