CVE-2026-3337 Timing Side-Channel in AES-CCM Tag Verification in AWS-LC
An attacker can determine authentication tag validity in AES-CCM decryption via timing analysis, potentially leaking sensitive information.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-3337?
CVE-2026-3337 is a high-severity vulnerability in AWS-LC, published on 2 Mar 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
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.
Weakness: CWE-208
Which versions are affected by CVE-2026-3337?
6 open source packages ship an affected version, including aws-lc-fips-sys and aws-lc-sys. It affects 3 products.
| Package | Affected | Fixed in |
|---|---|---|
aws-lc-fips-sys crates.io | From 0.13.0 | 0.13.12 |
aws-lc-fips-sys crates.io | From 0.13.0 | 0.13.12 |
aws-lc-fips-sys crates.io | From 0.13.0 | 0.13.12 |
aws-lc-sys crates.io | From 0.14.0 | 0.38.0 |
aws-lc-sys crates.io | From 0.14.0 | 0.38.0 |
aws-lc-sys crates.io | From 0.14.0 | 0.38.0 |
Products include Amazon Aws-Lc-Fips-Sys, Amazon Aws-Lc-Sys, Amazon Aws Libcrypto.
How do I fix CVE-2026-3337?
Upgrade aws-lc-fips-sys to 0.13.12 or later.
Is CVE-2026-3337 being exploited?
There is no known exploitation of CVE-2026-3337 in the wild and no public exploit code.
Sources
Also known as CLEANSTART-2026-OY93787, GHSA-65p9-r9h6-22vj, GHSA-frmv-5gcm-jwxh, MINI-26g6-3pcw-m295, MINI-2g5c-rhhr-3g39, MINI-2rgc-gjqv-68m9 and 15 more.