CVE-2021-23368

MEDIUMNVD 5.35.3—

5.3

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.

CVSS v3: 5.3
EG Score: 5.3(medium)
EPSS: 77.4%
KEV: Not listed

Published

April 12, 2021

Last Modified

November 21, 2024

References (20)

report@snykhttps://github.com/postcss/postcss/commit/8682b1e4e328432ba692bed52326e84439cec9e4
report@snykhttps://github.com/postcss/postcss/commit/b6f3e4d5a8d7504d553267f80384373af3a3dec5
report@snykhttps://lists.apache.org/thread.html/r00158f5d770d75d0655c5eef1bdbc6150531606c8f8bcb778f0627be%40%3Cdev.myfaces.apache.org%3E
report@snykhttps://lists.apache.org/thread.html/r16e295b4f02d81b79981237d602cb0b9e59709bafaa73ac98be7cef1%40%3Cdev.myfaces.apache.org%3E
report@snykhttps://lists.apache.org/thread.html/r49afb49b38748897211b1f89c3a64dc27f9049474322b05715695aab%40%3Cdev.myfaces.apache.org%3E
report@snykhttps://lists.apache.org/thread.html/r5acd89f3827ad9a9cad6d24ed93e377f7114867cd98cfba616c6e013%40%3Ccommits.myfaces.apache.org%3E
report@snykhttps://lists.apache.org/thread.html/r8def971a66cf3e375178fbee752e1b04a812a047cc478ad292007e33%40%3Cdev.myfaces.apache.org%3E
report@snykhttps://lists.apache.org/thread.html/rad5af2044afb51668b1008b389ac815a28ecea9eb75ae2cab5a00ebb%40%3Ccommits.myfaces.apache.org%3E
report@snykhttps://snyk.io/vuln/SNYK-JAVA-ORGWEBJARSNPM-1244795
report@snykhttps://snyk.io/vuln/SNYK-JS-POSTCSS-1090595
af854a3a-2127-422b-91ae-364da2661108https://github.com/postcss/postcss/commit/8682b1e4e328432ba692bed52326e84439cec9e4
af854a3a-2127-422b-91ae-364da2661108https://github.com/postcss/postcss/commit/b6f3e4d5a8d7504d553267f80384373af3a3dec5
af854a3a-2127-422b-91ae-364da2661108https://lists.apache.org/thread.html/r00158f5d770d75d0655c5eef1bdbc6150531606c8f8bcb778f0627be%40%3Cdev.myfaces.apache.org%3E
af854a3a-2127-422b-91ae-364da2661108https://lists.apache.org/thread.html/r16e295b4f02d81b79981237d602cb0b9e59709bafaa73ac98be7cef1%40%3Cdev.myfaces.apache.org%3E
af854a3a-2127-422b-91ae-364da2661108https://lists.apache.org/thread.html/r49afb49b38748897211b1f89c3a64dc27f9049474322b05715695aab%40%3Cdev.myfaces.apache.org%3E

Vendor Advisories for CVE-2021-23368(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

RHSA-2021:2438
Red Hat Product SecurityMedium
Red Hat Security Advisory: OpenShift Container Platform 4.8.2 bug fix and security update

Patch Availability(2)

Vendor / Ecosystem	Fixed in / Patch	Released	Source
redhat	quay/quay-rhel8:v3.6.0-62	2021-10-19	redhat
redhat	openshift4/ose-console:v4.8.0-202107010336.p0.git.188a490.assembly.stream	2021-07-27	redhat

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Affected Packages

(1 across 1 ecosystem)

npm(1)

Package	Vulnerable range	Fixed in	Dependents
postcss	—	8.2.10	—

Additional Vendor Advisories

(1)

Vendors that published advisories for this CVE beyond the curated set above. Broader coverage but minimal per-row detail — click through for the original advisory.

Red HatRHSA-2021:3917MODERATE2021-04-12
RHSA-2021:3917 — Moderate

Data Freshness Timeline

(refreshed 10× in last 7d / 20× in last 30d)

Every time one of our enrichment pipelines (NVD, MITRE cvelistV5, EPSS, CISA KEV, GHSA, OSV, vendor advisories) ran against this CVE. Most recent first.

2026-06-04 13:10 UTCepss_batch
2026-06-02 20:11 UTCepss_batch
2026-06-02 20:11 UTCepss_batch
2026-06-01 13:50 UTCepss_batch
2026-06-01 13:50 UTCepss_batch
2026-05-31 22:29 UTCepss_batch
2026-05-31 22:29 UTCepss_batch
2026-05-31 00:15 UTCepss_batch
2026-05-31 00:15 UTCepss_batch
2026-05-29 13:42 UTCepss_batch
2026-05-28 13:43 UTCepss_batch
2026-05-28 13:43 UTCepss_batch
2026-05-27 13:39 UTCepss_batch
2026-05-26 18:29 UTCEG score recompute
2026-05-26 18:29 UTCVendor advisory
2026-05-26 13:42 UTCepss_batch
2026-05-26 13:42 UTCepss_batch
2026-05-26 07:17 UTCepss_batch
2026-05-26 07:17 UTCepss_batch
2026-05-24 16:49 UTCepss_batch

Frequently asked(5)

What is CVE-2021-23368?

CVE-2021-23368 is a medium vulnerability published on April 12, 2021. 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.

When was CVE-2021-23368 disclosed?

CVE-2021-23368 was first published in the National Vulnerability Database on April 12, 2021, with the most recent update on November 21, 2024. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.

Is CVE-2021-23368 actively exploited?

CVE-2021-23368 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 77.4% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.

What is the CVSS score of CVE-2021-23368?

CVE-2021-23368 has a CVSS v3 base score of 5.3 (NVD).

How do I remediate CVE-2021-23368?

Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2021-23368, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2021-23368

Explore →

Is Your Infrastructure Affected by CVE-2021-23368?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Start Free Scan →Browse All CVEs