Skip to content
Patch Next
Sign inAdd to your agent

← Actionable
High, CVSS 7.5amended

MathJax Regular expression Denial of Service (ReDoS)

CVE-2023-39663GHSA-v638-q856-grg8

What to do

Vendor response not established. Follow the primary source's mitigation guidance and check back for a fix.

This page has no inventory attached, so it cannot say whether you are affected. A vendor fix is not proof that your deployment is fixed.

Add to your agent

Affected packages

  • npm mathjax

    Affected
    <= 2.7.9
    Fixed in
    no fixed version recorded

Sources

Severity and exploitation
Exploitation
No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.
CVSS
7.5 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS
  • CVE-2023-39663: 0.82% estimated exploitation activity in the next 30 days; percentile 57.29 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.
Source description

As published by the source; long descriptions are shortened.

Mathjax up to v2.7.9 was discovered to contain two Regular expression Denial of Service (ReDoS) vulnerabilities in MathJax.js via the components pattern and markdownPattern. NOTE: the vendor disputes this because the regular expressions are not applied to user input; thus, there is no risk.

Dates and revisions
Published by the source
Last modified by the source
Source last checked
  1. Revision 2 · amended ·

    Amended from ghsa record GHSA-v638-q856-grg8

  2. Revision 1 · created ·

    Published from osv record GHSA-v638-q856-grg8

Agent brief

Preview the exact text before you copy it. Commands are read-only suggestions; review them before running anything.

# Patch Next advisory brief: CVE-2023-39663

Advisory: MathJax Regular expression Denial of Service (ReDoS)
IDs: CVE-2023-39663, GHSA-v638-q856-grg8
Record: https://patchnext.com/advisories/cve-2023-39663 (revision 2, source checked 26 Oct 2026, 12:30 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 7.5)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor response not established. A vendor fix does not mean a deployment is fixed.

## Affected components
- npm mathjax: affected <= 2.7.9

## Suggested inspection (read-only)
- `npm ls mathjax --all`: lists every installed copy and version, including transitive ones. Run in the project root after `npm ci`.

## Supported action
No complete vendor fix is recorded. Follow the primary source's mitigation guidance and check this record again before closing anything.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on mathjax.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://osv.dev/vulnerability/GHSA-v638-q856-grg8 (OSV record GHSA-v638-q856-grg8 lists affected ranges: npm mathjax >=0 <=2.7.9)
- Verified: https://github.com/advisories/GHSA-v638-q856-grg8 (GitHub-reviewed advisory GHSA-v638-q856-grg8 lists affected ranges: npm mathjax >=0 <=2.7.9)

Commands are suggestions: review each one before running it.

Loading voting…