{"action":"Upgrade nltk to 3.10.3 or later.","affected":[{"fixed":"3.10.3","introduced":"0"}],"component":"nltk","cve_ids":["CVE-2026-78681"],"ecosystem":"PyPI","epss":0.00521,"exploited":false,"fixed_versions":["3.10.3"],"ghsa_id":"GHSA-97qj-x29f-37w7","id":"tcs_01M5KH73JNT4KEFQE28ZZNRXNF","modified_at":"2026-09-02T09:00:04.194017574Z","published_at":"2026-08-25T02:16:52.750Z","references":["https://osv.dev/vulnerability/PYSEC-2026-3748","https://www.vulncheck.com/advisories/nltk-before-entity-expansion-dos-via-elementtree","https://github.com/nltk/nltk/security/advisories/GHSA-97qj-x29f-37w7"],"severity":{"label":"high","score":7.5},"sources":[{"source":"osv","source_id":"PYSEC-2026-3748","url":"https://osv.dev/vulnerability/PYSEC-2026-3748"},{"source":"nvd","source_id":"CVE-2026-78681","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-78681"}],"summary":"NLTK versions before 3.10.3 use xml.etree.ElementTree to parse XML in multiple modules, which honors entity declarations in document DTDs. Attackers can craft XML payloads with nested entity declarati"}