{"id":"CVE-2026-109956","title":"NLTK through 3.10.3 contains a path traversal vulnerability in WekaClassifier that allows attackers to bypass nltk.pathsec containment by supplying unvalidated model paths","summary":"NLTK through 3.10.3 contains a path traversal vulnerability in WekaClassifier that allows attackers to bypass nltk.pathsec containment by supplying unvalidated model paths. Attackers controlling the model_filename or model argument can m…","severity":"high","cvss":7,"cvssVector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:H/A:L","cwe":["CWE-22"],"published":"2026-10-13","updated":"2026-10-13","sourceUpdated":"2026-10-13T14:17:34.520","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-109956","references":[{"url":"https://github.com/nltk/nltk/security/advisories/GHSA-j456-xh4h-cpf2","label":"disclosure@vulncheck.com"},{"url":"https://www.vulncheck.com/advisories/nltk-through-3.10.3-path-traversal-via-wekaclassifier-model-path","label":"disclosure@vulncheck.com"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-109956.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-109956"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2550515"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-109956"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-109956"},{"url":"https://github.com/nltk/nltk/pull/3863"},{"url":"https://github.com/nltk/nltk/commit/6a17606293fe9d3ea1006f99dd3fed2e2b25d519"},{"url":"https://github.com/nltk/nltk"},{"url":"https://github.com/nltk/nltk/releases/tag/v3.10.4"}],"tags":["nvd","csaf","vex","red-hat","cve.org","exploit-available","osv","pip"],"ingestedAt":"2026-10-13T14:29:01.855Z","vendor":"Red Hat","product":"Red Hat OpenShift AI (RHOAI)","affected":["lightspeed_core","openshift_lightspeed","ansible_automation_platform 2","openshift_ai_rhoai"],"epss":0.00318,"epssPercentile":0.24586,"exploitAvailable":true,"ssvc":{"exploitation":"poc","automatable":"no","technicalImpact":"partial","timestamp":"2026-10-26T19:46:23.846442Z"},"aliases":["GHSA-j456-xh4h-cpf2"],"ecosystem":"pip","patched":["nltk 3.10.4"],"scores":{"nvd":7,"osv":8.6},"slug":"CVE-2026-109956","body":"## Overview\n\nNLTK through 3.10.3 contains a path traversal vulnerability in WekaClassifier that allows attackers to bypass nltk.pathsec containment by supplying unvalidated model paths. Attackers controlling the model_filename or model argument can make the weka JVM write files via -d or probe files via -l outside allowed data roots.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Moderate · affected: Lightspeed Core, OpenShift Lightspeed, Red Hat Ansible Automation Platform 2, Red Hat OpenShift AI (RHOAI) · no fix planned: Red Hat Ansible Automation Platform 2, Lightspeed Core, OpenShift Lightspeed, Red Hat OpenShift AI (RHOAI) · updated 2026-10-16 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-109956.json)\n\n## Package advisory (CVE-2026-109956)\n\nAffected packages:\n\n- `nltk < 3.10.4`\n\nPatched in:\n\n- `nltk 3.10.4`\n\nSource: https://osv.dev/vulnerability/GHSA-j456-xh4h-cpf2","depth":"midnight","depthScore":51,"depthScoreParts":{"impact":38.5,"likelihood":0.1,"exploitation":12,"ransomware":0},"changes":[{"seq":229764,"id":"CVE-2026-109956","ts":1793047357587,"field":"exploit_available","old":"false","new":"true"}]}