CVE-2026-103923

KaTeX is a fast, easy-to-use JavaScript library for TeX math rendering on the web. From 0.11.0 until 0.18.2, KaTeX uses ordinary JavaScript property access for the renderer options object, the trust setting, default and processor setting metadata, and namespace lookup and group restoration, allowing inherited properties to be treated as explicitly supplied values. When Object.prototype is already polluted or an attacker controls the options object's prototype, attacker-controlled mathematical expressions can use an inherited trust value to enable trusted rendering and produce links capable of user-interaction cross-site scripting or loading attacker-selected external resources in a consuming application that inserts unsanitized KaTeX output into a page. KaTeX does not itself create the prototype pollution, and rendering an expression alone does not execute script. This issue is fixed in version 0.18.2.

CVSS

No CVSS.

References

Link	Resource
https://github.com/KaTeX/KaTeX/commit/0adf7e77db6915d991803b29699f82b1ccf8d4f4
https://github.com/KaTeX/KaTeX/pull/4260
https://github.com/KaTeX/KaTeX/releases/tag/v0.18.2
https://github.com/KaTeX/KaTeX/security/advisories/GHSA-238p-pmpm-9mq7

Configurations

No configuration.

History

01 Oct 2026, 18:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-01 18:17

Updated : 2026-10-06 02:17

NVD link : CVE-2026-103923

Mitre link : CVE-2026-103923

CVE.ORG link : CVE-2026-103923

JSON object : View

Products Affected

No product.

CWE

CWE-807

Reliance on Untrusted Inputs in a Security Decision

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