{"id":"CVE-2026-71513","aliases":["DEBIAN-CVE-2026-71513","EUVD-2026-64296","GHSA-5gh2-94qg-qppq","MGASA-2026-0340","PYSEC-2026-3867","UBUNTU-CVE-2026-71513","openSUSE-SU-2026:11587-1"],"status":"published","title":"NLTK 3.10.0 through 3.10.2 Remote Code Execution via AllowlistUnpickler Dotted-Name Bypass","description":"NLTK before 3.10.3 contains a remote code execution vulnerability in AllowlistUnpickler that validates only the pickle module string and not the global name, allowing attackers to resolve dotted names by attribute traversal to callables outside the allowlisted namespace. 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allowlisted_pickle_load.","severity":{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-12","score":0.01097,"percentile":0.66071,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-502"],"published":"2026-08-22T13:34:07Z","modified":"2026-10-28T02:30:33Z","fixes":[{"ecosystem":"PyPI","package":"nltk","fixed_in":["3.10.3"],"sources":["ghsa","osv"]},{"ecosystem":"Debian:14","package":"nltk","fixed_in":["3.10.3-1"],"sources":["osv"]}],"affected":[{"source":"ghsa","ecosystem":"PyPI","package":"nltk","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"3.10.0"},{"fixed":"3.10.3"}]}]},{"source":"osv","ecosystem":"Debian:12","package":"nltk","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.10.0-1","3.10.1-1","3.10.3-1","3.8-1","3.8.1-1","3.9.1-1","3.9.1-2","3.9.2-1","3.9.3-1"]},{"source":"osv","ecosystem":"Debian:13","package":"nltk","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.10.0-1","3.10.1-1","3.10.3-1","3.9.1-2","3.9.2-1","3.9.3-1"]},{"source":"osv","ecosystem":"Debian:14","package":"nltk","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.10.3-1"}]}],"versions":["3.10.0-1","3.10.1-1","3.9.1-2","3.9.2-1","3.9.3-1"]},{"source":"osv","ecosystem":"PyPI","package":"nltk","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"3.10.0"},{"fixed":"3.10.3"}]}],"versions":["3.10.0","3.10.1","3.10.2"]},{"source":"osv","ecosystem":"Mageia:10","package":"python-nltk","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.10.3-1.mga10"}]}],"bundled":18},{"source":"osv","ecosystem":"Mageia:9","package":"python-nltk","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.10.3-1.mga9"}]}],"bundled":18},{"source":"osv","ecosystem":"PyPI","package":"nltk","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"3.10.0"},{"fixed":"3.10.3"}]}],"versions":["3.10.0","3.10.1","3.10.2"]},{"source":"osv","ecosystem":"Ubuntu:Pro:14.04:LTS","package":"nltk","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.0~b9-0ubuntu4","2.0~b9-0ubuntu4.1~esm2","2.0~b9-0ubuntu4.1~esm4","2.0~b9-0ubuntu4.1~esm5","2.0~b9-0ubuntu4.1~esm6"]},{"source":"osv","ecosystem":"Ubuntu:Pro:16.04:LTS","package":"nltk","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.0.4-1","3.0.5-1","3.1-1","3.1-1ubuntu0.1","3.1-1ubuntu0.1+esm1","3.1-1ubuntu0.1+esm2","3.1-1ubuntu0.1+esm3","3.1-1ubuntu0.1+esm4"]},{"source":"osv","ecosystem":"Ubuntu:Pro:18.04:LTS","package":"nltk","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.2.4-1","3.2.5-1","3.2.5-1ubuntu0.1","3.2.5-1ubuntu0.1+esm1","3.2.5-1ubuntu0.1+esm2","3.2.5-1ubuntu0.1+esm3","3.2.5-1ubuntu0.1+esm4"]},{"source":"osv","ecosystem":"Ubuntu:Pro:20.04:LTS","package":"nltk","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.4.5-1","3.4.5-2","3.4.5-2ubuntu0.1~esm1","3.4.5-2ubuntu0.1~esm2","3.4.5-2ubuntu0.1~esm3","3.4.5-2ubuntu0.1~esm4"]},{"source":"osv","ecosystem":"Ubuntu:Pro:22.04:LTS","package":"nltk","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.5-1","3.6.5-1","3.6.7-1","3.7-1","3.7-1ubuntu0.1~esm1","3.7-1ubuntu0.1~esm2"]},{"source":"osv","ecosystem":"Ubuntu:Pro:24.04:LTS","package":"nltk","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.8.1-1","3.8.1-1ubuntu0.1~esm1","3.8.1-1ubuntu0.1~esm2"]},{"source":"osv","ecosystem":"Ubuntu:26.10","package":"nltk","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.9.2-1","3.9.3-1","3.10.0-1","3.10.1-1","3.10.3-1"]},{"source":"osv","ecosystem":"Ubuntu:Pro:26.04:LTS","package":"nltk","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.9.1-2","3.9.1-2build1","3.9.2-1","3.9.2-1ubuntu0.1~esm1","3.9.2-1ubuntu0.1~esm2"]},{"source":"osv","ecosystem":"openSUSE:Tumbleweed","package":"python-nltk","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.10.3-1.1"}]}],"bundled":2}],"products":[{"vendor":"nltk","product":"nltk"}],"references":[{"url":"https://github.com/nltk/nltk/commit/c3e37113742a1ebeeb4f2ca58941f320f98805ea","tags":["patch","Patch","fix","web","report"]},{"url":"https://github.com/nltk/nltk","tags":["product","Product","package","report"]},{"url":"https://github.com/nltk/nltk/blob/v3.10.2/nltk/picklesec.py#L119-L124","tags":["technical-description","Product","article","web"]},{"url":"https://www.vulncheck.com/advisories/nltk-through-remote-code-execution-via-allowlistunpickler-dotted-name-bypass","tags":["third-party-advisory","Third Party Advisory","Patch","advisory","web","report"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-71513","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-5gh2-94qg-qppq","tags":["advisory"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/71xxx/CVE-2026-71513.json","tags":["advisory"]},{"url":"https://security-tracker.debian.org/tracker/CVE-2026-71513","tags":["advisory"]},{"url":"https://advisories.mageia.org/MGASA-2026-0340.html","tags":["advisory"]},{"url":"https://bugs.mageia.org/show_bug.cgi?id=36186","tags":["report"]},{"url":"https://github.com/nltk/nltk/releases#release-v3.10.0","tags":["web"]},{"url":"https://github.com/nltk/nltk/releases#release-v3.10.2","tags":["web"]},{"url":"https://github.com/nltk/nltk/releases#release-v3.10.3","tags":["web"]},{"url":"https://pypi.org/project/nltk","tags":["package"]},{"url":"https://ubuntu.com/security/CVE-2026-71513","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-71513","tags":["report"]},{"url":"https://security-tracker.debian.org/tracker/cve-2026-71513","tags":["report"]},{"url":"https://github.com/cveproject/cvelistv5/tree/main/cves/2026/71xxx/cve-2026-71513.json","tags":["report"]},{"url":"https://github.com/nltk/nltk/blob/v3.10.2/nltk/picklesec.py#l119-l124","tags":["report"]},{"url":"https://nvd.nist.gov/vuln/detail/cve-2026-71513","tags":["report"]},{"url":"","tags":["advisory"]},{"url":"https://www.suse.com/security/cve/CVE-2026-12252","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2026-71513","tags":["web"]}],"sources":{"cve":[{"id":"CVE-2026-71513","title":"NLTK 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Please see the links.\n","status":"published","published":"2026-08-29T15:47:31Z","modified":"2026-08-29T16:00:02.787972151Z","updated_at":"2026-11-02T15:49:43.795591Z"},{"id":"openSUSE-SU-2026:11587-1","title":"python313-nltk-3.10.3-1.1 on GA media","description":"These are all security issues fixed in the python313-nltk-3.10.3-1.1 package on the GA media of openSUSE Tumbleweed.","status":"published","published":"2026-08-24T00:00:00Z","modified":"2026-08-26T18:23:38.201931468Z","updated_at":"2026-11-02T16:58:39.516824Z"}]}}