What is CVE-2026-3337?

CVE-2026-3337 is a medium-severity vulnerability in Amazon Aws-Lc-Fips-Sys, classified under CWE-208. CVSS score: 5.9/10. Published 2026-03-02.

How severe is CVE-2026-3337?

Medium severity. CVSS v3 base score is 5.9 out of 10.

Vulnerability in Amazon Aws-Lc-Fips-Sys

CVE-2026-3337

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.

Published 2026-03-02 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 5.9 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N.

EPSS exploit prediction

EPSS: 0.005 (41.1th percentile), scored 2026-10-20.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 41st percentile — 41.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.011 · newest: 0.005 · change: -0.006

Affected products

Weakness classification (CWE)

CWE-208

References

ff89ba41-3aa1-4d27-914a-91399e9639e5 (vendor-advisory, Vendor Advisory)
ff89ba41-3aa1-4d27-914a-91399e9639e5 (Release Notes, patch)
ff89ba41-3aa1-4d27-914a-91399e9639e5 (Vendor Advisory, third-party-advisory)

Frequently asked questions

What is CVE-2026-3337?: CVE-2026-3337 is a medium-severity vulnerability in Amazon Aws-Lc-Fips-Sys, classified under CWE-208. CVSS score: 5.9/10. Published 2026-03-02.
How severe is CVE-2026-3337?: Medium severity. CVSS v3 base score is 5.9 out of 10.