What is GHSA-cv2g-m8rr-888c?

GHSA-cv2g-m8rr-888c is a security advisory published by GitHub Security Advisories with High severity. NLTK versions before 3.9.4 contain an unbounded recursion vulnerability in JSONTaggedDecoder...

Which CVE IDs does GHSA-cv2g-m8rr-888c cover?

GHSA-cv2g-m8rr-888c covers the following CVE IDs: CVE-2026-66393. Each CVE has its own detail page on EchelonGraph Pulse with the synthesized EG score.

What is the CVSS v3 score of GHSA-cv2g-m8rr-888c?

GHSA-cv2g-m8rr-888c has a CVSS v3 base score of 7.5, published by GitHub Security Advisories.

GHSA-cv2g-m8rr-888cHighCVSS 7.5

NLTK versions before 3.9.4 contain an unbounded recursion vulnerability in JSONTaggedDecoder...

Vendor

GitHub Security Advisories

Published

August 22, 2026

Last Modified

August 22, 2026

🔗 CVE IDs covered (1)

CVE-2026-66393 →

📋 Description

NLTK versions before 3.9.4 contain an unbounded recursion vulnerability in JSONTaggedDecoder.decode_obj() that allows attackers to cause denial of service by supplying deeply nested JSON structures. Attackers can craft JSON payloads exceeding the recursion limit to trigger an unhandled RecursionError that crashes the Python process.

🔗 References (4)

https://github.com/nltk/nltk/security/advisories/GHSA-rf74-v2fm-23pw
https://nvd.nist.gov/vuln/detail/CVE-2026-66393
https://www.vulncheck.com/advisories/nltk-before-denial-of-service-via-jsontaggeddecoder
https://github.com/advisories/GHSA-cv2g-m8rr-888c