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Fencer Vulns
high 7.5

CVE-2021-23341 json

Regular Expression Denial of Service (ReDoS)

published 2021-02-18 5 y ago modified 2026-06-17 4 mo ago also GHSA-h4hr-7fg3-h35w , EUVD-2021-0662

cvss
7.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
3.2%
EPSS 3.2% chance of exploitation in 30 days, percentile 88%
public exploits
0
none known

Summary

The package prismjs before 1.23.0 are vulnerable to Regular Expression Denial of Service (ReDoS) via the prism-asciidoc, prism-rest, prism-tap and prism-eiffel components.

Patch / fix

  • npm prismjs 1.23.0
  • n/a prismjs 1.23.0
  • node-prismjs Debian 14, Debian 13, Debian 12 1.23.0+dfsg-1

debian advisories DEBIAN-CVE-2021-23341

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2021-23341 updated cvss 7.5

nodejs-prismjs: Regular expression denial of service via prism-asciidoc prism-rest prism-tap and prism-eiffel components

  • Red Hat OpenShift Service Mesh 2.0 servicemesh-grafana, servicemesh-grafana-prometheus Red Hat Ceph Storage 3 grafana Red Hat Ceph Storage 4 rhceph/rhceph-4-dashboard-rhel8 Red Hat OpenShift Container Platform 3.11 openshift3/grafana Red Hat OpenShift Container Platform 4 openshift4/ose-grafana
    affected: no fix planned “Will not fix”

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Exploit prediction

3.17% chance of exploitation in the next 30 days, higher than 88% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

  • github.com https://github.com/PrismJS/prism/issues/2583 referenced PoC, tagged "exploit" by a source, unverified
  • snyk.io https://snyk.io/vuln/SNYK-JS-PRISMJS-1076581 referenced PoC, tagged "exploit" by a source, unverified
  • snyk.io https://snyk.io/vuln/SNYK-JAVA-ORGWEBJARSNPM-1076582 referenced PoC, tagged "exploit" by a source, unverified
  • snyk.io https://snyk.io/vuln/SNYK-JAVA-ORGWEBJARS-1076583 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD 2.0 5.0 AV:N/AC:L/Au:N/C:N/I:N/A:P

Affected packages

ecosystem package affected fixed in
npm prismjs
<1.23.0
1.23.0

Affected products

  • n/a prismjs

Classification

Weakness
  • CWE-400 Uncontrolled Resource Consumption

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.