# 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.

- **Severity:** High 8.2 (`CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 2 Mar 2026
- **Updated:** 3 Mar 2026
- **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, MINI-7pm7-fc98-mxhg, MINI-8h4p-6gxm-cwjh, MINI-9qh3-f73v-gmp8, MINI-c4h3-pj8w-mqr8, MINI-c5r9-9xjx-x2gh, MINI-f9g5-m55h-m9mp, MINI-fh3c-pfgj-mhj2, MINI-jgg9-jj4g-v88v, MINI-jv8w-f224-4v3g, MINI-q27c-7j7p-v5xv, MINI-vgm6-fgww-cm6q, MINI-wf9g-444m-5cfx, MINI-wq6m-cph4-mp8r, RUSTSEC-2026-0043, RUSTSEC-2026-0045

## 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 (Observable Timing Discrepancy)

## 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 | Ecosystem | 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: 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.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-3337 and fix it if it is affected.

What it is: 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.
Exploitation: There is no known exploitation of CVE-2026-3337 in the wild and no public exploit code.

Affected packages and fixed versions:
- aws-lc-fips-sys (crates.io): affected from 0.13.0; fixed in 0.13.12
- aws-lc-fips-sys (crates.io): affected from 0.13.0; fixed in 0.13.12
- aws-lc-fips-sys (crates.io): affected from 0.13.0; fixed in 0.13.12
- aws-lc-sys (crates.io): affected from 0.14.0; fixed in 0.38.0
- aws-lc-sys (crates.io): affected from 0.14.0; fixed in 0.38.0
- aws-lc-sys (crates.io): affected from 0.14.0; fixed in 0.38.0

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-3337/ (Markdown: https://insights.sbomify.com/CVE-2026-3337/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-3337
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-3337
- OSV: https://osv.dev/vulnerability/CVE-2026-3337

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-3337/
Summaries are generated and may contain mistakes; the official description above is the record.