Alertas de Seguridad de la Información

M Alto vulnerabilidad

27/08/2026

[CVE-2026-81726] NLTK through 3.10.3 contains a path traversal vulnerability in model-artifact APIs that bypass paths…

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, PerceptronTagger, and maxent parameter APIs when pathsec is enabled.

nvdaltovulnerabilidad CVSS 7.0 NVD

M Alto vulnerabilidad

27/08/2026

[CVE-2026-81727] NLTK versions before 3.10.3 contain a filesystem containment bypass vulnerability in the Downloader.…

NLTK versions before 3.10.3 contain a filesystem containment bypass vulnerability in the Downloader.download and Downloader.incr_download methods that allows attackers to overwrite files outside the install root through pre-existing hardlinks. Attackers with write access to a shared downloader directory can create hardlinks pointing to outside-root files that are then overwritten during normal pac…

nvdaltovulnerabilidad CVSS 7.1 NVD

M Alto vulnerabilidad

27/08/2026

[CVE-2026-81722] nltk PorterStemmer in versions <= 3.10.2 (fixed in 3.10.3) contains an inefficient-algorithmic-compl…

nltk PorterStemmer in versions

nvdaltovulnerabilidad CVSS 7.5 NVD

M Alto vulnerabilidad

26/08/2026

[CVE-2026-80205] NLTK versions before 3.10.0 contain a regular expression denial of service vulnerability in Text.fin…

NLTK versions before 3.10.0 contain a regular expression denial of service vulnerability in Text.findall() and TokenSearcher.findall() methods that accept user-supplied regular expressions without validation or timeout. Attackers can supply crafted regex patterns that cause catastrophic backtracking, resulting in indefinite CPU saturation and denial of service to all users of the Python process.

nvdaltovulnerabilidad CVSS 7.5 NVD

M Alto vulnerabilidad

25/08/2026

[CVE-2026-79674] NLTK versions before 3.10.3 contain a path sandbox bypass vulnerability in corpus-reader constructor…

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.

nvdaltovulnerabilidad CVSS 8.2 NVD

M Alto vulnerabilidad

25/08/2026

[CVE-2026-78680] NLTK versions before 3.10.3 fail to use validated absolute paths when invoking the Graphviz dot bina…

NLTK versions before 3.10.3 fail to use validated absolute paths when invoking the Graphviz dot binary in dependencygraph.dot2img and AlignedSent._repr_svg_, allowing attackers to execute arbitrary code by placing a malicious dot binary in the search path or current working directory. Attackers can exploit bare-name binary resolution on Windows via the current working directory or on Unix-like sys…

nvdaltovulnerabilidad CVSS 7.8 NVD

M Alto vulnerabilidad

25/08/2026

[CVE-2026-78681] NLTK versions before 3.10.3 use xml.etree.ElementTree to parse XML in multiple modules, which honors…

NLTK versions before 3.10.3 use xml.etree.ElementTree to parse XML in multiple modules, which honors entity declarations in document DTDs. Attackers can craft XML payloads with nested entity declarations that expand from hundreds of bytes to megabytes in memory, causing denial of service.

nvdaltovulnerabilidad CVSS 7.5 NVD

M Alto vulnerabilidad

25/08/2026

[CVE-2026-78682] NLTK before 3.10.3 contains a server-side request forgery vulnerability in nltk.pathsec.urlopen (and…

NLTK before 3.10.3 contains a server-side request forgery vulnerability in nltk.pathsec.urlopen (and callers nltk.data.load, nltk.downloader.Downloader.index/download) when an HTTP proxy is configured. pathsec.urlopen validates the requested hostname locally, but proxy-handler inheritance disables the safe HTTP/HTTPS handlers so the actual fetch is performed by the proxy against a destination that…

nvdaltovulnerabilidad CVSS 7.5 NVD

M Alto vulnerabilidad

22/08/2026

Vulnerabilidad alta en NLTK 3.9.2 y anteriores permite inyección de código malicioso

NLTK (Natural Language Toolkit) anterior a versión 3.9.3 no valida la integridad de paquetes descargados antes de su extracción, permitiendo ataques de intermediario (MITM) o envenenamiento DNS para inyectar contenido malicioso. Afecta principalmente a empresas en LATAM que usan este framework en pipelines de procesamiento de lenguaje natural, análisis de datos y sistemas de chatbots.

nvdaltovulnerabilidad CVSS 7.1 NVD

M Alto vulnerabilidad

22/08/2026

Vulnerabilidad alta en NLTK: lectura arbitraria de archivos locales en versiones anteriores a 3.10.0

NLTK anterior a la versión 3.10.0 contiene una vulnerabilidad que permite la lectura arbitraria de archivos locales mediante StreamBackedCorpusView, eludiendo los controles de pathsec.ENFORCE al llamar directamente a builtins.open(). Un atacante que controle el parámetro fileid puede acceder a archivos sensibles del sistema, credenciales de aplicaciones y datos confidenciales, independientemente de la configuración de seguridad habilitada. Afecta principalmente a aplicaciones de procesamiento de lenguaje natural desplegadas en entornos empresariales de LATAM.

nvdaltovulnerabilidad CVSS 7.5 NVD

M Alto vulnerabilidad

22/08/2026

Vulnerabilidad de recursión no acotada en NLTK anterior a 3.9.4 permite denegación de servicio

NLTK versiones anteriores a 3.9.4 contienen una vulnerabilidad de recursión no acotada en JSONTaggedDecoder.decode_obj() que permite a atacantes causar denegación de servicio mediante estructuras JSON profundamente anidadas. Un payload malicioso que exceda el límite de recursión desencadena una excepción RecursionError no controlada que causa el fallo del proceso Python. Afecta aplicaciones de procesamiento de lenguaje natural en infraestructuras LATAM, incluyendo sistemas de análisis de datos y chatbots empresariales.

nvdaltovulnerabilidad CVSS 7.5 NVD

M Alto vulnerabilidad

22/08/2026

[CVE-2026-62384] NLTK versions before 3.10.2 contain a symlink-based sandbox bypass in FramenetCorpusReader that allo…

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 validation guard and are resolved to files outside the intended corpus root when accessed via frame_by_name(), _…

nvdaltovulnerabilidad CVSS 7.5 NVD

M Alto vulnerabilidad

22/08/2026

[CVE-2026-62388] NLTK versions before 3.10.0 default to ENFORCE=False in pathsec.py, causing all security validation …

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 active when manually enabled.

nvdaltovulnerabilidad CVSS 7.5 NVD

M Alto vulnerabilidad

22/08/2026

[CVE-2026-71513] NLTK before 3.10.3 contains a remote code execution vulnerability in AllowlistUnpickler that validat…

NLTK before 3.10.3 contains a remote code execution vulnerability in AllowlistUnpickler that validates only the pickle module string and not the global name, allowing attackers to resolve dotted names by attribute traversal to callables outside the allowlisted namespace. Attackers can craft untrusted transition-parser models that execute arbitrary commands when TransitionParser.parse loads the mod…

nvdaltovulnerabilidad CVSS 8.8 NVD

M Alto vulnerabilidad

20/08/2026

[CVE-2026-72818] The URLS regular expression in nltk/tokenize/casual.py, compiled into TweetTokenizer.WORD_RE and app…

The URLS regular expression in nltk/tokenize/casual.py, compiled into TweetTokenizer.WORD_RE and applied by TweetTokenizer.tokenize, contains a naked-domain branch whose domain-label prefix [a-z0-9]+(?:[.\-][a-z0-9]+)* is unbounded. Input consisting of many alternating label separators can be partitioned in exponentially many ways, and because the branch also requires a trailing top-level domain t…

nvdaltovulnerabilidad CVSS 7.5 NVD

M Alto vulnerabilidad

24/07/2026

[CVE-2025-71408] NLTK (Natural Language Toolkit) before version 3.9.3 contains an eval injection vulnerability in the…

NLTK (Natural Language Toolkit) before version 3.9.3 contains an eval injection vulnerability in the nltk.collocations module that allows an attacker who controls command-line arguments to execute arbitrary Python code. When collocations.py is invoked directly, the __main__ block passes command-line arguments directly to eval() as suffixes of BigramAssocMeasures without allowlist validation or san…

nvdaltovulnerabilidad CVSS 7.8 NVD

N Alto vulnerabilidad

04/07/2026

[CVE-2026-12252] In nltk/nltk versions 3.9.3 and earlier, five Stanford interface classes (StanfordPOSTagger, Stanfor…

In nltk/nltk versions 3.9.3 and earlier, five Stanford interface classes (StanfordPOSTagger, StanfordNERTagger, StanfordParser, StanfordDependencyParser, and StanfordNeuralDependencyParser) are vulnerable to untrusted JAR code execution. These classes accept user-controllable JAR paths and execute them via the `java()` function, which invokes `subprocess.Popen()` without integrity verification. Th…

nvdaltovulnerabilidad CVSS 7.8 NVD

N Alto vulnerabilidad

30/06/2026

[CVE-2026-12243] NLTK version 3.9.4 is vulnerable to a path traversal attack due to an incomplete fix for GitHub Issu…

NLTK version 3.9.4 is vulnerable to a path traversal attack due to an incomplete fix for GitHub Issue #3504. The `_UNSAFE_NO_PROTOCOL_RE` regex in `nltk/data.py` checks for literal `../` sequences but fails to account for percent-encoded traversal sequences such as `..%2f`. The `url2pathname()` function decodes these sequences after the validation step, allowing an attacker to bypass the protectio…

nvdaltovulnerabilidad CVSS 7.5 NVD

N Alto vulnerabilidad

22/06/2026

[CVE-2026-54293] NLTK (Natural Language Toolkit) is a suite of open source Python modules, data sets, and tutorials s…

NLTK (Natural Language Toolkit) is a suite of open source Python modules, data sets, and tutorials supporting research and development in Natural Language Processing. Prior to 3.10.0-rc1, nltk.data.load() in NLTK is vulnerable to path traversal via URL-encoded path separators and traversal segments when using the nltk: URL scheme. The unsafe-path regex check is performed before url2pathname() deco…

nvdaltovulnerabilidad CVSS 7.5 NVD

M Alto vulnerabilidad

17/06/2026

[CVE-2026-12199] A vulnerability in `nltk.app.wordnet_app` up to version 3.9.3 allows unauthenticated remote shutdown…

A vulnerability in `nltk.app.wordnet_app` up to version 3.9.3 allows unauthenticated remote shutdown of the local WordNet Browser HTTP server when started in its default mode. The server listens on all interfaces and processes a specific unauthenticated GET request (`/SHUTDOWN%20THE%20SERVER`) to terminate the process immediately via `os._exit(0)`. This results in a denial of service, impacting se…

nvdaltovulnerabilidad CVSS 7.5 NVD