CVE-2026-12252 PUBLISHED

Untrusted JAR Code Execution in Multiple Stanford Interface Classes in nltk/nltk

Assigner: @huntr_ai
Reserved: 15.06.2026 Published: 04.07.2026 Updated: 04.07.2026

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. This vulnerability is identical to CVE-2026-0848, which was fixed for StanfordSegmenter by adding SHA256 verification. However, the fix was not applied to these additional classes, leaving them susceptible to arbitrary code execution when loading untrusted JAR files.

Metrics

CVSS Vector: CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
CVSS Score: 7.8

Product Status

Vendor nltk
Product nltk/nltk
Versions
  • affected from unspecified to latest (incl.)

References

Problem Types

  • CWE-94 Improper Control of Generation of Code CWE