Skip to content
Fencer Vulns
medium 5.3

CVE-2021-23368 json

Regular Expression Denial of Service (ReDoS)

published 2021-04-12 5 y ago modified 2026-06-17 4 mo ago also GHSA-hwj9-h5mp-3pm3 , EUVD-2021-1108

cvss
5.3
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
3.5%
EPSS 3.5% chance of exploitation in 30 days, percentile 89%
public exploits
0
none known

Summary

The package postcss from 7.0.0 and before 8.2.10 are vulnerable to Regular Expression Denial of Service (ReDoS) during source map parsing.

Patch / fix

  • npm postcss 7.0.36, 8.2.10
  • n/a postcss 8.2.10
  • node-postcss Debian 14, Debian 13, Debian 12 8.2.1+~cs5.3.23-6

debian advisories DEBIAN-CVE-2021-23368

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-2021-23368 updated cvss 5.3

nodejs-postcss: Regular expression denial of service during source map parsing

  • Red Hat Logging Subsystem for Red Hat OpenShift openshift-logging/kibana6-rhel8
    affected: no fix available “Fix deferred”
  • Red Hat OpenShift Service Mesh 2.0 servicemesh-grafana, servicemesh-prometheus, servicemesh-grafana-prometheus
    affected: no fix available
  • Red Hat Advanced Cluster Management for Kubernetes 2 console, search-ui, grc-ui-rhel8, application-ui
    affected: no fix available “Fix deferred”
  • Red Hat OpenShift Container Platform 4 kibana, openshift4/ose-grafana, openshift4/ose-thanos-rhel9, openshift4/ose-logging-kibana6, golang-github-prometheus-prometheus
    affected: no fix available, no fix planned “Will not fix”
  • Red Hat Virtualization 4 ovirt-web-ui, cockpit-ovirt-uiplugin, cockpit-ovirt-dashboard, ovirt-engine-ui-extensions
    affected: no fix planned “Will not fix”
  • Red Hat Quay v3 quay/quay-rhel8 v3.6.0-62
    fixed: vendor fix RHSA-2021:3917
  • Red Hat OpenShift Container Platform 4.8 openshift4/ose-console v4.8.0-202107010336.p0.git.188a490.assembly.stream
    fixed: vendor fix RHSA-2021:2438
  • Red Hat Quay v3 quay/clair-rhel8 v3.6.0-70, quay/quay-builder-rhel8 v3.6.0-44, quay/quay-operator-rhel8 v3.6.0-43, quay/quay-operator-bundle v3.6.0-48, quay/quay-bridge-operator-rhel8 v3.6.0-40, quay/quay-bridge-operator-bundle v3.6.0-35, +3 more Red Hat Ansible Automation Platform 1.2 postcss Red Hat OpenShift Container Platform 3.11 kibana Red Hat OpenShift Container Platform 4.8 openshift4/ose-cli v4.8.0-202106291725.p0.git.1077b05.assembly.stream, openshift4/ose-pod v4.8.0-202107161820.p0.git.051ac4f.assembly.stream, openshift4/ose-etcd v4.8.0-202106152230.p0.git.aefa6bf.assembly.stream, openshift4/ose-tests v4.8.0-202107131424.p0.git.0d958c3.assembly.stream, openshift4/ose-coredns v4.8.0-202106291913.p0.git.642b46e.assembly.stream, openshift4/ose-grafana v4.8.0-202106291913.p0.git.b987e4b.assembly.stream, +135 more
    not affected: vulnerable code not present

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

3.51% chance of exploitation in the next 30 days, higher than 89% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

  • snyk.io https://snyk.io/vuln/SNYK-JS-POSTCSS-1090595 referenced PoC, tagged "exploit" by a source, unverified
  • snyk.io https://snyk.io/vuln/SNYK-JAVA-ORGWEBJARSNPM-1244795 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 3.1 5.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
NVD 3.1 5.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
NVD 2.0 5.0 AV:N/AC:L/Au:N/C:N/I:N/A:P
GitHub 3.1 5.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

Affected packages

ecosystem package affected fixed in
npm postcss
>=7.0.0, <7.0.36
>=8.0.0, <8.2.10
7.0.36
8.2.10

Affected products

  • n/a postcss

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.