PatchTheCVECVE-2026-79676: NLTK versions before 3.10.3 contain a path traversal vulnerability in corpus readers that reopen root-derived
CVE-2026-79676 is a medium-severity flaw (CVSS 5.9) affecting nltk. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
NLTK versions before 3.10.3 contain a path traversal vulnerability in corpus readers that reopen root-derived paths using built-in open() instead of nltk.pathsec.open(), allowing symlinks to escape trusted roots. Attackers who stage symlinked corpus files under a trusted data root can disclose outside-root content through normal corpus reader methods like channels(), domains(), and synonyms().
Why this priority
- Public exploit reference
- Remotely exploitable, no login, no user action
A fixed release or distro patch exists.
Risk facts
| CVSS score | 5.9 (Medium) |
| Attack vector | Network (remote) |
| Attack complexity | High |
| Privileges needed | None |
| User interaction | None |
| EPSS exploit chance | 0.4% (top 61%) |
| CISA exploited list | No |
| Weakness | CWE-22 |
| Published | 2026-08-25 |
| Last modified | 2026-08-31 |
Last updated 2026-08-31 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Am I affected?
Timeline
- Published CVE record published
- Updated Record last modified
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2026-79676?
nltk: upgrade to 3.10.3. Exact commands for each OS are on this page.
Is CVE-2026-79676 being exploited?
CVE-2026-79676 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.
What does CVE-2026-79676 affect?
CVE-2026-79676 affects nltk. Severity is medium (CVSS 5.9). NLTK versions before 3.10.3 contain a path traversal vulnerability in corpus readers that reopen root-derived paths using built-in open() instead of nltk.pathsec.open(), allowing symlinks to escape trusted roots. Attackers who stage symlink
How urgent is CVE-2026-79676?
Priority 40/100. Public exploit reference; Remotely exploitable, no login, no user action
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