CVE-2026-78680

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.

CVSS v3 7.8 HIGH

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/nltk/nltk/security/advisories/GHSA-6hwm-xvph-95vm
https://www.vulncheck.com/advisories/nltk-before-arbitrary-code-execution-via-graphviz-dot-binary
https://github.com/nltk/nltk/security/advisories/GHSA-6hwm-xvph-95vm

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-25 02:16

Updated : 2026-08-25 13:19

NVD link : CVE-2026-78680

Mitre link : CVE-2026-78680

CVE.ORG link : CVE-2026-78680

JSON object : View

Products Affected

No product.

CWE

CWE-426

Untrusted Search Path

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