EUVD-2026-65525

NLTK: JVM argument injection bypass via per-call options in the NLTK Stanford wrappers incomplete fix of CVE-2026-12841...

EUVD-2026-65226

NLTK: Uncontrolled search path when invoking the Graphviz 'dot' binary...

CVE-2019-14751_PoC

CVE-2019-14751PoC A Proof of Concept for CVE-2019-14751 Vulnerability Description NLTK Downloader before version 3.5 is vulnerable to a directory traversal, allowing attackers to write arbitrary files via a ../ dot dot slash in an NLTK package ZIP archive that is mishandled during extraction. For...

CVE-2026-63310

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. Mitigation Upgrade the nltk...

CVE-2026-81723

A flaw was found in NLTK. This vulnerability, specifically in the XMLCorpusView.readxmlfragment function, allows a remote attacker to cause severe CPU consumption and a denial of service DoS by providing specially crafted, malformed XML corpus files. The flaw occurs because the system repeatedly...

CVE-2026-81727

A flaw was found in NLTK. This vulnerability, a filesystem containment bypass, allows a local attacker with write access to a shared downloader directory to create special links hardlinks that point to files outside the intended installation area. When a package is extracted, these hardlinks can...

CVE-2026-81725

A flaw was found in NLTK, specifically within the Pl196xCorpusReader component. A remote attacker can exploit this by supplying malformed Text Encoding Initiative TEI blocks containing numerous unmatched opening tags. This triggers a regular expression denial of service ReDoS vulnerability, causi...

CVE-2026-81724

A flaw was found in NLTK. This uncontrolled recursion vulnerability in nltk.featstruct.FeatStructReader allows unauthenticated attackers to cause a denial of service. Attackers can achieve this by supplying deeply nested feature-structure input, which can lead to applications crashing when parsin...

CVE-2026-81722

A flaw was found in the nltk PorterStemmer component. A remote attacker could exploit this vulnerability by providing a specially crafted, untrusted token. The inefficient algorithmic complexity in the stemming process, specifically within the isconsonant and measure helper functions, causes...

EUVD-2026-66397

NLTK before 3.10.3 contains a regular expression denial of service ReDoS vulnerability in the tgrep module. The tgrepnodeaction function compiles user-supplied regular expressions embedded in /regex/ pattern nodes and executes them via re.search against tree node labels without any validation or...

CVE-2026-63312

A flaw was found in NLTK. This vulnerability, specifically within the StreamBackedCorpusView component, allows an attacker to bypass security enforcement by directly calling builtins.open instead of the intended pathsec.open. By controlling the fileid argument, an attacker can read arbitrary loca...

CVE-2026-71514

A flaw was found in NLTK. This path traversal vulnerability in the CrubadanCorpusReader component allows an attacker, who controls a corpus package, to disclose file contents outside the intended corpus directory. This occurs because a specially crafted input can bypass security checks, leading t...

CVE-2026-62385

A flaw was found in NLTK. This path traversal vulnerability, located in the FramenetCorpusReader and NKJPCorpusReader components, allows an attacker to read arbitrary XML files accessible to the application. This can be achieved by supplying unsafe selectors or poisoned index state, exploiting...

CVE-2026-62383

A flaw was found in nltk. A local attacker can exploit a symlink-based vulnerability in the IPIPANCorpusReader methods. By placing a symbolic link in the corpus root directory and invoking specific methods, an attacker can bypass security validation and read arbitrary files accessible to the...

CVE-2026-72818

A flaw was found in NLTK. The TweetTokenizer component, used for processing social media text, contains a regular expression vulnerability. A remote unauthenticated attacker can provide specially crafted input containing many alternating label separators, causing the regular expression to backtra...

CVE-2026-71513

A flaw was found in NLTK. A remote attacker can achieve remote code execution by crafting untrusted transition-parser models. This vulnerability exists in the AllowlistUnpickler, which incorrectly validates only the pickle module string and not the global name. This allows attackers to bypass the...

CVE-2026-62388

A flaw was found in NLTK. The software's default settings in pathsec.py cause security checks to only issue warnings rather than actively preventing malicious actions. This allows attackers to bypass safeguards designed to prevent unauthorized access to files path traversal and the execution of...

CVE-2026-70626

A flaw was found in NLTK. This vulnerability allows a local attacker to read arbitrary files outside of the intended directory. By placing symbolic links symlinks within the corpus root, an attacker can bypass path validation in the CorpusReader.open function, which does not properly account for...

CVE-2026-66393

A flaw was found in NLTK. A remote attacker can exploit an unbounded recursion vulnerability in the JSONTaggedDecoder.decodeobj function by supplying deeply nested JSON structures. This can cause the Python process to crash, leading to a denial of service. Mitigation To mitigate this vulnerabilit...

CVE-2026-81723

NLTK versions before 3.10.3 contain a quadratic CPU exhaustion vulnerability in XMLCorpusView.readxmlfragment that rescans accumulated XML fragments on every 1 KiB block read. Attackers can provide malformed XML corpus files to cause severe CPU consumption and denial of service through affected...