Read the docs
TI-2026-65767 Aliases CVE-2026-103923GHSA-238p-pmpm-9mq7

KaTeX: Existing prototype pollution can bypass trust restrictions

Priority LOW 11CWE-807Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
Active
Attack complexity
Low
Attack requirements
Present
Impact type
—
Confidentiality · integrity · availability
None · None · None
Fix status
Partial Red Hat: 3 without a fix

Attack profile from CVSS 4.0 · CNA. Fix status from CNA, GitHub and Red Hat.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.003 22nd percentileScored 2026-11-07
Fix Partial KaTeX (KaTeX): 0.18.2katex (npm): 0.18.2Red Hat: 3 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
KaTeXKaTeX0.11.0 to before 0.18.20.18.2Patch availableCNA
—katex (npm)0.11.0 to before 0.18.20.18.2Patch availableGHSA-238p-pmpm-9mq7
  • KaTeX VendorKaTeX Affected 0.11.0 to before 0.18.2 Fixed in 0.18.2 Patch available CNA
  • katex (npm) Vendor— Affected 0.11.0 to before 0.18.2 Fixed in 0.18.2 Patch available GHSA-238p-pmpm-9mq7

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:a:katex:katex:*:*:*:*:*:*:*:*——KaTeX
  • cpe:2.3:a:katex:katex:*:*:*:*:*:*:*:* Versions — — ·KaTeX

Remediation

  • Fix · CNA KaTeX (KaTeX) Fixed in 0.18.2
  • Fix · GHSA-238p-pmpm-9mq7 katex (npm) Fixed in 0.18.2 Advisory →

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Build of Podman DesktopAffectedNo fix yet: Fix deferred
Red Hat OpenShift AI (RHOAI)AffectedNo fix yet: Fix deferred
Red Hat OpenShift Dev SpacesAffectedNo fix yet: Fix deferred
Not affected: 1 product
  • Red Hat Hardened Images

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-103923
  2. 2026-10-06 CISA SSVC decision points changed
  3. 2026-10-06 Alias added: GHSA-238p-pmpm-9mq7
  4. 2026-10-06 Fix available: npm/[email protected] · GHSA-238p-pmpm-9mq7
  5. 2026-10-06 CVSS score added · GHSA-238p-pmpm-9mq7
  6. 2026-10-06 Weakness changed · GHSA-238p-pmpm-9mq7
  7. 2026-10-06 6 new references · GHSA-238p-pmpm-9mq7

References

Advisory 1

Other 5

  • TI-2024-18803 KaTeX's maxExpand bypassed by Unicode sub/superscripts CVSS 3.1MEDIUM 6.5
  • TI-2025-16992 \htmlData does not validate attribute names in KaTeX CVSS 3.1HIGH 7.2
  • TI-2024-18802 KaTeX's maxExpand bypassed by \edef CVSS 3.1MEDIUM 6.5
  • TI-2024-18804 KaTeX's \includegraphics does not escape filename CVSS 3.1MEDIUM 6.3
  • TI-2024-18805 KaTeX is missing normalization of the protocol in URLs allows bypassing forbidden protocols CVSS 3.1MEDIUM 5.5

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences