What is CVE-2026-4428?

CVE-2026-4428 is a high-severity vulnerability in Aws Aws-lc, classified under Improper Check for Certificate Revocation. CVSS score: 7.4/10. Published 2026-03-19.

How severe is CVE-2026-4428?

High severity. CVSS v3 base score is 7.4 out of 10.

Vulnerability in Aws Aws-lc

CVE-2026-4428

A logic error in CRL distribution point validation in AWS-LC before 1.71.0 causes partitioned CRLs to be incorrectly rejected as out of scope, which allows a revoked certificate to bypass certificate revocation checks. To remediate this…

EPSS: 0.000 (7.6th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.4 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N.

Affected products

Aws Aws-lc — versions 1.24.0
Aws Aws-lc-fips — versions 3.0.0

Weakness classification (CWE)

CWE-299 — Improper Check for Certificate Revocation

References

aws.amazon.com/security/security-bulletins/2026-010-AWS/ (vendor-advisory)
github.com/aws/aws-lc/releases/tag/v1.71.0 (patch)

Frequently asked questions

What is CVE-2026-4428?: CVE-2026-4428 is a high-severity vulnerability in Aws Aws-lc, classified under Improper Check for Certificate Revocation. CVSS score: 7.4/10. Published 2026-03-19.
How severe is CVE-2026-4428?: High severity. CVSS v3 base score is 7.4 out of 10.