CVE-2026-4428: AWS-LC · Improper Check for Certificate Revocation
Affects AWS-LCSource CVE Database V5
Not known to be exploited · CVSS 7.4 High : upgrade to 1.71.0 soon.
Data as of 31 Oct 2026, 20:20 UTC
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 17% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 1.71.0, 3.3.0
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:NExploitation evidence
Disclosed: evidence found.
CVE published 19 Mar 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 31 Oct 2026.
What to do
Upgrade AWS-LC to 1.71.0; AWS-LC-FIPS to 3.3.0.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| AWSAWS-LC | Affected
| Fixed in
|
| AWSAWS-LC-FIPS | Affected
| Fixed in
|
GitHubaws/aws-lcpkg:github/aws/aws-lcOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Users should upgrade to AWS-LC version 1.71.0 or AWS-LC-FIPS-3.3.0 to remediate this issue. No other mitigations are indicated by the vendor advisory.
Description
CVE-2026-4428 is a logic error in AWS-LC versions before 1.71.0 that causes partitioned Certificate Revocation Lists (CRLs) to be incorrectly rejected as out of scope. This flaw allows revoked certificates to bypass revocation checks, potentially enabling use of invalid certificates. The issue is fixed by upgrading to AWS-LC 1.71.0 or AWS-LC-FIPS-3.3.0.