# CVE-2026-78680

## Summary

- **CVE ID:** CVE-2026-78680
- **Severity:** HIGH
- **CVSS Score:** 8.5 (CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N)
- **CWE:** CWE-426
- **Published:** Aug 25, 2026
- **Last Modified:** Aug 25, 2026

## Description

NLTK versions before 3.10.3 fail to use validated absolute paths when invoking the Graphviz dot binary in dependencygraph.dot2img and AlignedSent._repr_svg_, allowing attackers to execute arbitrary code by placing a malicious dot binary in the search path or current working directory. Attackers can exploit bare-name binary resolution on Windows via the current working directory or on Unix-like systems via relative PATH entries to execute their binary instead of the legitimate Graphviz tool.

## Affected Products

- nltk — nltk (0)
- nltk — nltk (3.10.3)

## References

- [CNA](https://github.com/nltk/nltk/security/advisories/GHSA-6hwm-xvph-95vm)
- [CNA](https://www.vulncheck.com/advisories/nltk-before-arbitrary-code-execution-via-graphviz-dot-binary)

## Exploitation Prediction (EPSS)

- **EPSS Score:** 0.12%
- **EPSS Percentile:** 2.1

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_Exported from OnDuty AI Vulnerability Intelligence on 2026-09-10._