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Vulnerability record · CVE-2026-3338 · published 2 March 2026

CVE-2026-3338: Amazon aws-lc-sys improper verification of cryptographic signature vulnerability

Amazon · Aws Lc Sys

Improper signature validation in PKCS7_verify() in AWS-LC allows an unauthenticated user to bypass signature verification when processing PKCS7 objects with Authenticated Attributes. Customers of AWS services do not need to take action. Applications using AWS-LC should upgrade to AWS-LC version 1.69.0.

8.7 CVSS 4.0 High EPSS 0.38% · top 70.2% CWE-347 · Improper verification of cryptographic signature
8.7CVSS 4.0 base score
0.38%EPSS exploitation probability, 30 days
NoNot in CISA KEV
2Affected product versions listed by NVD
7References
15 Jul 2026Last modified by NVD

Description

Improper signature validation in PKCS7_verify() in AWS-LC allows an unauthenticated user to bypass signature verification when processing PKCS7 objects with Authenticated Attributes. Customers of AWS services do not need to take action. Applications using AWS-LC should upgrade to AWS-LC version 1.69.0.

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:

Affected products

2 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://aws.amazon.com/security/security-bulletins/2026-005-AWS/ Vendor Advisory
https://github.com/aws/aws-lc/releases/tag/v1.69.0 Release Notes
https://github.com/aws/aws-lc/security/advisories/GHSA-jchq-39cv-q4wj Vendor Advisory
https://access.redhat.com/errata/RHSA-2026:5459
https://access.redhat.com/security/cve/CVE-2026-3338
https://bugzilla.redhat.com/show_bug.cgi?id=2444025
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-3338.json

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2026-3338), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.