CVE catalog
CVE-2026-109956
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 m
- Severity
- High · CVSS 8.3
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:H/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - Published
- Updated
- Source
- [NVD] · [CVE record]
- EPSS
- 0.32% · Oct 25, 2026
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 make the weka JVM write files via -d or probe files via -l outside allowed data roots.
Vulnerable and fixed packages
Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.
| Distribution | Package | Release | Version | Status |
|---|---|---|---|---|
| Debian | nltk | sid | 3.10.3-1 | vulnerable |
| Debian | nltk | forky | 3.10.3-1 | vulnerable |
| Debian | nltk | trixie | 3.9.1-2 | vulnerable |
| Debian | nltk | bookworm | 3.8-1 | vulnerable |
Fixed-version evidence
| Distribution | Package | Type | Release | Fixed version | Urgency | Origin | Bugs |
|---|---|---|---|---|---|---|---|
| Debian | nltk | source | sid | (unfixed) | not yet assigned | Not reported | [1150904] |
| Debian | nltk | source | forky | (unfixed) | not yet assigned | Not reported | [1150904] |
| Debian | nltk | source | trixie | (unfixed) | not yet assigned | Not reported | [1150904] |
| Debian | nltk | source | bookworm | (unfixed) | not yet assigned | Not reported | [1150904] |
Notes
[trixie] nltk: Minor issue [bookworm] nltk: Minor issue; can be fixed in next update
OpenFactory catalog packages
[Debian 12 (Bookworm)]
- [python3-nltk]Affected
Source package: [nltk]
Details (2)
3.8-1· all · bookwormAffected
nvd · nltk · debian · bookworm; nvd · nltk · debian · 12
3.8-1· all · bookwormAffected
nvd · nltk · debian · bookworm; nvd · nltk · debian · 12
[Debian 13 (Trixie)]
- [python3-nltk]Affected
Source package: [nltk]
Details (2)
3.9.1-2· all · trixieAffected
nvd · nltk · debian · 13
3.9.1-2· all · trixieAffected
nvd · nltk · debian · 13
Observed:
References
- [https://github.com/nltk/nltk/security/advisories/GHSA-j456-xh4h-cpf2]
- [https://nvd.nist.gov/vuln/detail/CVE-2026-109956]
- [https://osv.dev/vulnerability/DEBIAN-CVE-2026-109956]
- [https://security-tracker.debian.org/tracker/CVE-2026-109956]
- [https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-109956.json]
- [https://www.vulncheck.com/advisories/nltk-through-3.10.3-path-traversal-via-wekaclassifier-model-path]
[Debian Security Tracker] · [FIRST EPSS] · [National Vulnerability Database (NVD)] · [OSV Package Vulnerability Database] · [Red Hat security advisories and VEX]