{"id":"CVE-2026-12252","aliases":["DEBIAN-CVE-2026-12252","EUVD-2026-41656","GHSA-9r6g-266r-89x4","PYSEC-2026-2085","UBUNTU-CVE-2026-12252","openSUSE-SU-2026:11587-1"],"status":"published","title":"Untrusted JAR Code Execution in Multiple Stanford Interface Classes in nltk/nltk","description":"In nltk/nltk versions 3.9.3 and earlier, five Stanford interface classes (StanfordPOSTagger, StanfordNERTagger, StanfordParser, StanfordDependencyParser, and StanfordNeuralDependencyParser) are vulnerable to untrusted JAR code execution. These classes accept user-controllable JAR paths and execute them via the `java()` function, which invokes `subprocess.Popen()` without integrity verification. This vulnerability is identical to CVE-2026-0848, which was fixed for StanfordSegmenter by adding SHA256 verification. However, the fix was not applied to these additional classes, leaving them susceptible to arbitrary code execution when loading untrusted JAR files.","severity":{"version":"3.0","score":7.8,"vector":"CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-10","score":0.00195,"percentile":0.09226,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-94"],"published":"2026-07-04T00:58:58Z","modified":"2026-10-28T02:30:51Z","fixes":[{"ecosystem":"PyPI","package":"nltk","fixed_in":["3.9.4"],"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":"0"},{"fixed":"3.9.4"}]}]},{"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":"0"},{"fixed":"3.9.4"}]}],"versions":["0.8","0.9","0.9.3","0.9.4","0.9.5","0.9.6","0.9.7","0.9.8","0.9.9","2.0.1","2.0.1rc1","2.0.1rc2-git","2.0.1rc3","2.0.1rc4","2.0.2","2.0.3","2.0.4","2.0.5","2.0b4","2.0b5","2.0b6","2.0b7","2.0b8","2.0b9","3.0.0","3.0.0b1","3.0.0b2","3.0.1","3.0.2","3.0.3","3.0.4","3.0.5","3.1","3.2","3.2.1","3.2.2","3.2.3","3.2.4","3.2.5","3.3","3.4","3.4.1","3.4.2","3.4.3","3.4.4","3.4.5","3.5","3.5b1","3.6","3.6.1","3.6.2","3.6.3","3.6.4","3.6.5","3.6.6","3.6.7","3.7","3.8","3.8.1","3.9","3.9.1","3.9.2","3.9.3","3.9b1"]},{"source":"osv","ecosystem":"PyPI","package":"nltk","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.9.4"}]}],"versions":["0.8","0.9","0.9.3","0.9.4","0.9.5","0.9.6","0.9.7","0.9.8","0.9.9","2.0.1","2.0.1rc1","2.0.1rc2-git","2.0.1rc3","2.0.1rc4","2.0.2","2.0.3","2.0.4","2.0.5","2.0b4","2.0b5","2.0b6","2.0b7","2.0b8","2.0b9","3.0.0","3.0.0b1","3.0.0b2","3.0.1","3.0.2","3.0.3","3.0.4","3.0.5","3.1","3.2","3.2.1","3.2.2","3.2.3","3.2.4","3.2.5","3.3","3.4","3.4.1","3.4.2","3.4.3","3.4.4","3.4.5","3.5","3.5b1","3.6","3.6.1","3.6.2","3.6.3","3.6.4","3.6.5","3.6.6","3.6.7","3.7","3.8","3.8.1","3.9","3.9.1","3.9.2","3.9.3","3.9b1"]},{"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:25.10","package":"nltk","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.9.1-2"]},{"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"},{"vendor":"nltk","product":"nltk/nltk"}],"references":[{"url":"https://huntr.com/bounties/f5c93982-0cc9-4e2e-bb85-1b6ab29a2efb","tags":["exploit","Exploit","Third Party Advisory","web","evidence","report"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-12252","tags":["advisory"]},{"url":"https://github.com/nltk/nltk/pull/3743","tags":["web"]},{"url":"https://github.com/nltk/nltk/commit/006f4b83d430147b067b81e2cddd226d6fa405c8","tags":["web"]},{"url":"https://github.com/nltk/nltk/commit/24777f0cb8c33ed2839d16e0f8169a3c312a6806","tags":["web"]},{"url":"https://github.com/nltk/nltk/releases/tag/v3.10.3","tags":["web"]},{"url":"https://github.com/pypa/advisory-database/tree/main/vulns/nltk/PYSEC-2026-2085.yaml","tags":["web"]},{"url":"https://github.com/advisories/GHSA-9r6g-266r-89x4","tags":["advisory"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/12xxx/CVE-2026-12252.json","tags":["advisory"]},{"url":"https://security-tracker.debian.org/tracker/CVE-2026-12252","tags":["advisory"]},{"url":"https://github.com/nltk/nltk","tags":["package"]},{"url":"https://ubuntu.com/security/CVE-2026-12252","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-12252","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-2026-12252","title":"Untrusted JAR Code Execution in Multiple Stanford Interface Classes in nltk/nltk","description":"In nltk/nltk versions 3.9.3 and earlier, five Stanford interface classes (StanfordPOSTagger, StanfordNERTagger, StanfordParser, StanfordDependencyParser, and StanfordNeuralDependencyParser) are vulnerable to untrusted JAR code execution. These classes accept user-controllable JAR paths and execute them via the `java()` function, which invokes `subprocess.Popen()` without integrity verification. This vulnerability is identical to CVE-2026-0848, which was fixed for StanfordSegmenter by adding SHA256 verification. However, the fix was not applied to these additional classes, leaving them susceptible to arbitrary code execution when loading untrusted JAR files.","status":"published","published":"2026-07-04T00:58:58.93Z","modified":"2026-07-06T18:33:11.411Z","cvss":[{"version":"3.0","score":7.8,"vector":"CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","level":"high","assessor":"cna"}],"cwes":["CWE-94"],"updated_at":"2026-11-02T14:19:48.461833Z"}],"euvd":[{"id":"EUVD-2026-41656","description":"In nltk/nltk versions 3.9.3 and earlier, five Stanford interface classes (StanfordPOSTagger, StanfordNERTagger, StanfordParser, StanfordDependencyParser, and StanfordNeuralDependencyParser) are vulnerable to untrusted JAR code execution. These classes accept user-controllable JAR paths and execute them via the `java()` function, which invokes `subprocess.Popen()` without integrity verification. This vulnerability is identical to CVE-2026-0848, which was fixed for StanfordSegmenter by adding SHA256 verification. However, the fix was not applied to these additional classes, leaving them susceptible to arbitrary code execution when loading untrusted JAR files.","status":"published","published":"2026-07-04T00:58:58Z","modified":"2026-07-06T18:33:11Z","cvss":[{"version":"3.0","score":7.8,"vector":"CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","level":"high"}],"updated_at":"2026-11-02T18:20:12.791563Z"}],"ghsa":[{"id":"GHSA-9r6g-266r-89x4","title":"NLTK Stanford wrapper classes execute untrusted JAR files without verification","description":"In nltk/nltk versions 3.9.3 and earlier, five Stanford interface classes (StanfordPOSTagger, StanfordNERTagger, StanfordParser, StanfordDependencyParser, and StanfordNeuralDependencyParser) are vulnerable to untrusted JAR code execution. These classes accept user-controllable JAR paths and execute them via the `java()` function, which invokes `subprocess.Popen()` without integrity verification. This vulnerability is identical to CVE-2026-0848, which was fixed for StanfordSegmenter by adding SHA256 verification. However, the fix was not applied to these additional classes, leaving them susceptible to arbitrary code execution when loading untrusted JAR files.","status":"published","published":"2026-07-04T03:31:03Z","modified":"2026-10-02T18:30:18Z","cvss":[{"version":"3.0","score":7.8,"vector":"CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","level":"high"}],"cwes":["CWE-94"],"updated_at":"2026-11-02T14:41:24.739884Z"}],"nvd":[{"id":"CVE-2026-12252","description":"In nltk/nltk versions 3.9.3 and earlier, five Stanford interface classes (StanfordPOSTagger, StanfordNERTagger, StanfordParser, StanfordDependencyParser, and StanfordNeuralDependencyParser) are vulnerable to untrusted JAR code execution. These classes accept user-controllable JAR paths and execute them via the `java()` function, which invokes `subprocess.Popen()` without integrity verification. This vulnerability is identical to CVE-2026-0848, which was fixed for StanfordSegmenter by adding SHA256 verification. However, the fix was not applied to these additional classes, leaving them susceptible to arbitrary code execution when loading untrusted JAR files.","status":"published","published":"2026-07-04T02:16:23.603Z","modified":"2026-10-25T15:10:00.147Z","cvss":[{"version":"3.0","score":7.8,"vector":"CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","level":"high","assessor":"secondary"}],"cwes":["CWE-94"],"updated_at":"2026-11-02T14:12:27.541515Z"}],"osv":[{"id":"CVE-2026-12252","title":"Untrusted JAR Code Execution in Multiple Stanford Interface Classes in nltk/nltk","description":"In nltk/nltk versions 3.9.3 and earlier, five Stanford interface classes (StanfordPOSTagger, StanfordNERTagger, StanfordParser, StanfordDependencyParser, and StanfordNeuralDependencyParser) are vulnerable to untrusted JAR code execution. These classes accept user-controllable JAR paths and execute them via the `java()` function, which invokes `subprocess.Popen()` without integrity verification. This vulnerability is identical to CVE-2026-0848, which was fixed for StanfordSegmenter by adding SHA256 verification. However, the fix was not applied to these additional classes, leaving them susceptible to arbitrary code execution when loading untrusted JAR files.","status":"published","published":"2026-07-04T00:58:58.93Z","modified":"2026-10-28T02:30:51.527924972Z","cvss":[{"version":"3.0","score":7.8,"vector":"CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","level":"high"}],"cwes":["CWE-94"],"updated_at":"2026-11-02T15:44:57.354194Z"},{"id":"DEBIAN-CVE-2026-12252","description":"In nltk/nltk versions 3.9.3 and earlier, five Stanford interface classes (StanfordPOSTagger, StanfordNERTagger, StanfordParser, StanfordDependencyParser, and StanfordNeuralDependencyParser) are vulnerable to untrusted JAR code execution. These classes accept user-controllable JAR paths and execute them via the `java()` function, which invokes `subprocess.Popen()` without integrity verification. This vulnerability is identical to CVE-2026-0848, which was fixed for StanfordSegmenter by adding SHA256 verification. However, the fix was not applied to these additional classes, leaving them susceptible to arbitrary code execution when loading untrusted JAR files.","status":"published","published":"2026-07-04T02:16:23.603Z","modified":"2026-10-26T11:47:29.404886261Z","cvss":[{"version":"3.0","score":7.8,"vector":"CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","level":"high"}],"updated_at":"2026-11-02T15:45:51.374409Z"},{"id":"GHSA-9r6g-266r-89x4","title":"NLTK Stanford wrapper classes execute untrusted JAR files without verification","description":"In nltk/nltk versions 3.9.3 and earlier, five Stanford interface classes (StanfordPOSTagger, StanfordNERTagger, StanfordParser, StanfordDependencyParser, and StanfordNeuralDependencyParser) are vulnerable to untrusted JAR code execution. These classes accept user-controllable JAR paths and execute them via the `java()` function, which invokes `subprocess.Popen()` without integrity verification. This vulnerability is identical to CVE-2026-0848, which was fixed for StanfordSegmenter by adding SHA256 verification. However, the fix was not applied to these additional classes, leaving them susceptible to arbitrary code execution when loading untrusted JAR files.","status":"published","published":"2026-07-04T03:31:03Z","modified":"2026-10-02T18:55:37.071322102Z","cvss":[{"version":"3.0","score":7.8,"vector":"CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","level":"high"}],"cwes":["CWE-94"],"updated_at":"2026-11-02T15:46:44.225359Z"},{"id":"PYSEC-2026-2085","description":"In nltk/nltk versions 3.9.3 and earlier, five Stanford interface classes (StanfordPOSTagger, StanfordNERTagger, StanfordParser, StanfordDependencyParser, and StanfordNeuralDependencyParser) are vulnerable to untrusted JAR code execution. These classes accept user-controllable JAR paths and execute them via the `java()` function, which invokes `subprocess.Popen()` without integrity verification. This vulnerability is identical to CVE-2026-0848, which was fixed for StanfordSegmenter by adding SHA256 verification. However, the fix was not applied to these additional classes, leaving them susceptible to arbitrary code execution when loading untrusted JAR files.","status":"published","published":"2026-07-04T02:16:23.603Z","modified":"2026-10-15T14:45:11.790616373Z","cvss":[{"version":"3.0","score":7.8,"vector":"CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","level":"high"}],"updated_at":"2026-11-02T15:52:55.537808Z"},{"id":"UBUNTU-CVE-2026-12252","description":"In nltk/nltk versions 3.9.3 and earlier, five Stanford interface classes (StanfordPOSTagger, StanfordNERTagger, StanfordParser, StanfordDependencyParser, and StanfordNeuralDependencyParser) are vulnerable to untrusted JAR code execution. These classes accept user-controllable JAR paths and execute them via the `java()` function, which invokes `subprocess.Popen()` without integrity verification. This vulnerability is identical to CVE-2026-0848, which was fixed for StanfordSegmenter by adding SHA256 verification. However, the fix was not applied to these additional classes, leaving them susceptible to arbitrary code execution when loading untrusted JAR files.","status":"published","published":"2026-07-04T02:16:00Z","modified":"2026-10-17T12:58:04.864683929Z","cvss":[{"version":"3.0","score":7.8,"vector":"CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","level":"high"}],"updated_at":"2026-11-02T16:56:00.592716Z"},{"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"}]}}