Vulnerability · Published Mar 2, 2026 · Assigned by AMZN

CVE-2026-3337Timing Side-Channel in AES-CCM Tag Verification in AWS-LC

Medium 5.9

In plain English

A medium-severity security flaw in AWS-LC from AWS. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 1.1% (higher than 65% of all known vulnerabilities).

Severity (CVSS 3.1)5.9Medium

Exploit odds (30 days)1.1%top 34.9% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

Observable timing discrepancy in AES-CCM decryption in AWS-LC allows an unauthenticated user to potentially determine authentication tag validity via timing analysis. The impacted implementations are through the EVP CIPHER API: EVP_aes_128_ccm, EVP_aes_192_ccm, and EVP_aes_256_ccm. Customers of AWS services do not need to take action. Applications using AWS-LC should upgrade to AWS-LC version 1.69.0.

Affected products (as reported)

Vendor	Product	Versions
AWS	AWS-LC	1.21.0 – before 1.69.0
AWS	AWS-LC-FIPS	3.0.0 – before 3.2.0

Weakness: CWE-208 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N

References

https://aws.amazon.com/security/security-bulletins/2026-005-AWS/ vendor-advisory
https://github.com/aws/aws-lc/releases/tag/v1.69.0 patch
https://github.com/aws/aws-lc/security/advisories/GHSA-frmv-5gcm-jwxh third-party-advisory