Read the docs
TI-2026-00628 Aliases CVE-2026-0847GHSA-68j8-pq59-fqgm

Path Traversal in nltk/nltk

Priority HIGH 72CWE-22Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Information disclosure
Confidentiality · integrity · availability
High · None · None
Fix status
Partial Red Hat: 2 fixed, 4 without a fix

Attack profile from CVSS 3.1 · NVD. Fix status from CNA, GitHub and Red Hat. Impact type from CWE-22 and the CVSS impact.

Summary

A vulnerability in NLTK versions up to and including 3.9.2 allows arbitrary file read via path traversal in multiple CorpusReader classes, including WordListCorpusReader, TaggedCorpusReader, and BracketParseCorpusReader. These classes fail to properly sanitize or validate file paths, enabling attackers to traverse directories and access sensitive files on the server. This issue is particularly critical in scenarios where user-controlled file inputs are processed, such as in machine learning APIs, chatbots, or NLP pipelines. Exploitation of this vulnerability can lead to unauthorized access to sensitive files, including system files, SSH private keys, and API tokens, and may potentially escalate to remote code execution when combined with other vulnerabilities.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.01 63rd percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Partial nltk (PyPI): 3.9.3Red Hat: 2 advisoriesRed Hat: 2 fixed, 4 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
nltknltk/nltkup to latest—No fix listedCNA
—nltk (PyPI)before 3.9.33.9.3Patch availableGHSA-68j8-pq59-fqgm
  • nltk/nltk Vendornltk Affected up to latest Fixed in — No fix listed CNA
  • nltk (PyPI) Vendor— Affected before 3.9.3 Fixed in 3.9.3 Patch available GHSA-68j8-pq59-fqgm

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:nltk:nltk:*:*:*:*:*:*:*:*up to 3.9.2Vulnerablenltk
  • cpe:2.3:a:nltk:nltk:*:*:*:*:*:*:*:* Versions up to 3.9.2 Vulnerable ·nltk

Remediation

  • Fix · GHSA-68j8-pq59-fqgm nltk (PyPI) Fixed in 3.9.3 Advisory →

Red Hat 2 advisories

  • RHSA-2026:19712 Released 2026-05-20 · Red Hat rating Critical
    RHOAI 3.3.3 - Red Hat OpenShift AI
    • Red Hat OpenShift AI 3.3 registry.redhat.io/rhoai/odh-built-in-detector-rhel9, registry.redhat.io/rhoai/odh-dashboard-rhel9, registry.redhat.io/rhoai/odh-data-science-pipelines-argo-argoexec-rhel9 +33
  • RHSA-2026:10184 Released 2026-04-23 · Red Hat rating Important
    RHOAI 2.25.5 - Red Hat OpenShift AI
    • Red Hat OpenShift AI 2.25 registry.redhat.io/rhoai/odh-caikit-nlp-rhel9, registry.redhat.io/rhoai/odh-caikit-tgis-serving-rhel9, registry.redhat.io/rhoai/odh-dashboard-rhel9 +47

Vendor assessments

Red Hat

Red Hat rating: Important. Red Hat's page for this CVE →

ProductStatusPlan or fix
Lightspeed CoreAffectedNo fix yet
OpenShift LightspeedAffectedNo fix planned: Will not fix
Red Hat Ansible Automation Platform 2AffectedNo fix yet
Red Hat OpenShift AI (RHOAI)AffectedNo fix planned: Will not fix
Red Hat OpenShift AI 2.25Fixed RHSA-2026:10184
Red Hat OpenShift AI 3.3Fixed RHSA-2026:19712
Not affected: 4 products
  • OpenShift Lightspeed
  • Red Hat Ansible Automation Platform 2
  • Red Hat OpenShift AI 2.25
  • Red Hat OpenShift AI 3.3

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-0847
  2. 2026-10-03 Alias added: GHSA-68j8-pq59-fqgm
  3. 2026-11-04 Fix available: PyPI/[email protected] · GHSA-68j8-pq59-fqgm
  4. 2026-11-04 5 new references · GHSA-68j8-pq59-fqgm

References

Exploit 1

Advisory 1

Other 7

  • TI-2026-00629 Arbitrary Code Execution in NLTK StanfordSegmenter via Untrusted JAR Loading CVSS 3.0CRITICAL 10.0
  • TI-2025-12800 Zip Slip Vulnerability in nltk/nltk Leading to Remote Code Execution CVSS 3.0CRITICAL 10.0
  • TI-2026-55173 NLTK before 3.10.3 JVM Argument Injection via Per-Call Options CVSS 4.0CRITICAL 9.3
  • TI-2026-55155 NLTK before 3.10.3 Remote Code Execution via Unsafe Pickle Deserialization CVSS 4.0CRITICAL 9.3
  • TI-2026-56370 nltk PorterStemmer before 3.10.3 Quadratic-time DoS CVSS 4.0HIGH 8.7
  • TI-2026-55172 NLTK 3.10.2 Path Traversal via corpus-reader constructors CVSS 4.0HIGH 8.8
See all 41 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences