9.1

CVE-2026-4428: aws aws-lc

CVSS: 9.1v4.0CriticalAwaiting analysis
AliasesGHSA-9f94-5g5w-gf6rRUSTSEC-2026-0042RUSTSEC-2026-0048
Published 19-03-2026Last modified 25-03-2026
Open JSON

Vulnerability summary

CVE-2026-4428 is a critical (CVSS 9.1) vulnerability in aws aws-lc. EPSS estimates a 0.27% chance of exploitation in the next 30 days, higher than 17.6% of scored vulnerabilities.

Overall risk
70/100
0100
High · default modelHow is this calculated?
CVSS score
9.1/10
010
Critical · v4.0 (CVE.org)
EPSS score
0.27%
0%100%
Low · +0.02 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 19-03-2026
    PublishedVulnerability first disclosed.
  2. 25-03-2026
    Last modifiedVulnerability information updated.

Description

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 issue, users should upgrade to AWS-LC 1.71.0 or AWS-LC-FIPS-3.3.0.

CVSS metrics

5 scores · 3 sources · 2 versions

EPSS trend

Probability

0.27%

Chance of exploitation in the next 30 days

Percentile

18%

Versus all other CVEs

30-day change

+0.02 pp

From 0.25% on 18-09-2026

18-09-202618-10-2026
EPSS score
0.27%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Aws2 products
Crates.Io2 products
  • aws-lc-fips-sys≥ 0.13.0, < 0.13.13
  • aws-lc-sys≥ 0.15.0, < 0.39.0

2 vendors · 4 products

References

9 links