{"action":"Upgrade nltk to 3.10.3 or later.","affected":[{"fixed":"3.10.3","introduced":"0"}],"component":"nltk","cve_ids":["CVE-2026-81724"],"ecosystem":"PyPI","epss":0.00456,"exploited":false,"fixed_versions":["3.10.3"],"ghsa_id":"GHSA-cw6x-m8jw-qmrh","id":"tcs_01M5KH724YC5Q4Q8K4ZM8B0V87","modified_at":"2026-09-01T09:15:03.464962431Z","published_at":"2026-08-27T17:21:03.100Z","references":["https://osv.dev/vulnerability/PYSEC-2026-3739","https://www.vulncheck.com/advisories/nltk-before-3.10.3-denial-of-service-via-uncontrolled-recursion","https://github.com/nltk/nltk/security/advisories/GHSA-cw6x-m8jw-qmrh"],"severity":{"label":"medium","score":5.3},"sources":[{"source":"osv","source_id":"PYSEC-2026-3739","url":"https://osv.dev/vulnerability/PYSEC-2026-3739"},{"source":"nvd","source_id":"CVE-2026-81724","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-81724"}],"summary":"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 fe"}