CVE-2026-115351

Mistune from 3.2.1 before 3.3.0 contains a CSS injection vulnerability that allows attackers controlling markdown input to inject arbitrary style declarations via the unvalidated figwidth option of the figure directive. Attackers can append declarations like background:url() to the rendered figure style attribute, forcing victim browsers to send requests to attacker servers and leak attribute values.

CVSS v3 4.7 MEDIUM

4.7^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/lepture/mistune/security/advisories/GHSA-xmwc-wjpr-q378
https://www.vulncheck.com/advisories/mistune-3.2.1-before-3.3.0-css-injection-via-figure-directive-figwidth-option
https://github.com/lepture/mistune/security/advisories/GHSA-xmwc-wjpr-q378

Configurations

No configuration.

History

29 Oct 2026, 12:17

Type	Values Removed	Values Added
References	~~() https://github.com/lepture/mistune/security/advisories/GHSA-xmwc-wjpr-q378 -~~	() https://github.com/lepture/mistune/security/advisories/GHSA-xmwc-wjpr-q378 -

22 Oct 2026, 19:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-22 19:17

Updated : 2026-10-29 12:17

NVD link : CVE-2026-115351

Mitre link : CVE-2026-115351

CVE.ORG link : CVE-2026-115351

JSON object : View

Products Affected

No product.

CWE

CWE-94

Improper Control of Generation of Code ('Code Injection')

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