{"action":"Upgrade nltk to 3.10.3 or later.","affected":[{"fixed":"3.10.3","introduced":"0"}],"component":"nltk","cve_ids":["CVE-2026-81722"],"ecosystem":"PyPI","epss":0.00521,"exploited":false,"fixed_versions":["3.10.3"],"ghsa_id":"GHSA-ww6m-cw3f-q94g","id":"tcs_01M5KH720Q4E6137R4DDW81YYP","modified_at":"2026-09-01T09:15:04.064770060Z","published_at":"2026-08-27T17:21:02.800Z","references":["https://osv.dev/vulnerability/PYSEC-2026-3738","https://www.vulncheck.com/advisories/nltk-porterstemmer-before-3.10.3-quadratic-time-dos","https://github.com/nltk/nltk/security/advisories/GHSA-ww6m-cw3f-q94g"],"severity":{"label":"high","score":7.5},"sources":[{"source":"osv","source_id":"PYSEC-2026-3738","url":"https://osv.dev/vulnerability/PYSEC-2026-3738"},{"source":"nvd","source_id":"CVE-2026-81722","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-81722"}],"summary":"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"}