CVE-2026-12074

Name of the Vulnerable Software and Affected Versions NLTK (affected versions not specified)

Description An issue exists in the FramenetCorpusReader.frame(name) function where a caller-supplied frame name is interpolated into an XML file path. This allows a path traversal attack using ../ sequences to escape the corpus root and read arbitrary XML files that the process has access to. The issue bypasses the nltk.pathsec sandbox and the ENFORCE=True mode because the path is read using the builtin open() function instead of CorpusReader.open(), meaning nltk.pathsec.validate path() is never invoked.

Similar behavior is found in the doc() function, which uses the filename field from index entries, and the lexical-unit file loader, which uses the lexUnit ID attribute. These can be exploited via a malicious or modified FrameNet corpus index.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.