Published CVEs with severity, CVSS, affected vendors and products, exploitation status, remediation deadlines, and primary sources.
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.
NLTK before 3.10.3 contains a regular expression denial of service vulnerability in Pl196xCorpusReader that allows attackers to cause quadratic CPU consumption by supplying malformed TEI blocks with many unmatched opening tags. Attackers can exploit lazy regex patterns in the read_block method through public APIs like words() and tagged_words() to force repeated rescans and achieve near-quadratic runtime growth.
NLTK before 3.10.3 contains an uncontrolled recursion vulnerability in nltk.featstruct.FeatStructReader that allows unauthenticated attackers to cause a denial of service by supplying deeply nested feature-structure input. Attackers can craft trivial payloads with nested brackets that exceed Python's recursion limit and raise an unhandled RecursionError, crashing applications that parse user-supplied feature structures or feature grammars.
NLTK versions before 3.10.3 contain a quadratic CPU exhaustion vulnerability in XMLCorpusView._read_xml_fragment() 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 readers like BNCCorpusReader.
nltk PorterStemmer in versions <= 3.10.2 (fixed in 3.10.3) contains an inefficient-algorithmic-complexity denial of service in PorterStemmer.stem(). The _is_consonant() helper walks backward over the entire run of trailing 'y' characters on every call, and _measure() invokes it for each stem position, causing O(n^2) behavior. A single ~20-50 KB untrusted token consisting of a long run of the letter 'y' followed by a matching suffix (e.g., 'ness') can pin a CPU core for seconds to minutes, causing availability impact.
openssl_encrypt before 1.4.9 fails to validate KDF cost parameters in encrypted file metadata and keystore headers, allowing attackers to trigger unbounded memory allocation. Attackers can craft malicious encrypted files declaring arbitrarily large Argon2, scrypt, or balloon KDF parameters to exhaust system memory and crash the process without authentication.
openssl_encrypt before 1.4.9 fails to validate the memory_cost parameter from identity file protection blocks, allowing attackers to trigger out-of-memory conditions during key derivation. Attackers with write access to local identity stores can craft malicious identity files with excessive memory_cost values that cause the host to crash when unlocking identities before authentication.
openssl_encrypt before 1.4.9 executes untrusted third-party plugins with insufficient controls: the plugin signature policy defaulted to WARN, so an unsigned/unverifiable non-built-in plugin was compiled and executed in the host process at import time, before the runtime sandbox is installed. The only default gate was an incomplete, bypassable AST denylist. If a user is induced to load an attacker's plugin, this results in arbitrary code execution with the privileges of the user running openssl_encrypt. Fixed in 1.4.9 by defaulting the signature policy to ENFORCE for non-built-in plugins.
openssl_encrypt versions before 1.4.9 use under-parameterized PBKDF2-HMAC-SHA256 with only 100,000 iterations to protect PQC keyfile private keys and 10,000 iterations for dual-encryption file-password verification. Attackers who obtain keyfiles or encrypted files can brute-force wrapping passwords offline using GPU or ASIC acceleration.
openssl_encrypt (pip package openssl-encrypt) before 1.4.9 contains two weaknesses in the portable USB drive feature, whose threat model treats the removable drive as untrusted (attacker with physical write access). USBDriveCreator._verify_integrity_file only validates files listed in the manifest, so files added to the drive — including a root-level autorun payload — are not detected and integrity verification still passes. Additionally, a globally constant, source-embedded KDF salt (_LEGACY_FIXED_SALT) is used to derive the drive encryption key for any drive lacking a per-drive salt file, defeating precomputation resistance and enabling an offline rainbow-table attack.
openssl_encrypt (pip: openssl-encrypt) versions before 1.4.9 contain a path traversal flaw in PluginSandbox._is_safe_path, which authorized file access using a bare string-prefix match. A sandboxed plugin without the READ_FILES permission could read or write another plugin's directory that merely shares a name prefix (e.g., .../plugins/foobar matching allowed .../plugins/foo), breaking per-plugin isolation within the same user. Fixed by matching each allowed directory exactly or with a trailing path separator.
openssl_encrypt (pip package openssl-encrypt) versions <= 1.4.8 do not redact the keyserver bearer token passed as the positional argument to 'keyserver set-token' in the --debug argv dump, because sanitize_argv_for_debug fails to sanitize it. As a result the token is printed in cleartext to stderr under --debug (even without --unsafe-show-secrets), persisting the credential in logs and terminal history. Fixed in 1.4.9.