Vulnerability in Amazon Aws-Lc-Sys

CVE-2026-3338

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.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N.

EPSS exploit prediction

EPSS: 0.004 (33.6th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 34th percentile — 33.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-3338: held from 0.008 to 0.004.

EPSS over last 30 days · oldest: 0.008 · newest: 0.004 · change: -0.004

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-3338?
CVE-2026-3338 is a high-severity vulnerability in Amazon Aws-Lc-Sys, classified under Improper Verification of Cryptographic Signature. CVSS score: 7.5/10. Published 2026-03-02.
How severe is CVE-2026-3338?
High severity. CVSS v3 base score is 7.5 out of 10.