RUSTSEC-2026-0045 (CVE-2026-3337)
Vulnerability from osv_rustsec – Published: 2026-03-02 12:00 – Updated: 2026-03-21 06:45 – Source websiteObservable 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. aws-lc-sys contains
code from AWS-LC. Applications using aws-lc-sys should upgrade to the most
recent release of aws-lc-sys.
Workarounds
In the special cases of using AES-CCM with (M=4, L=2), (M=8, L=2), or
(M=16, L=2), applications can workaround this issue by using AES-CCM through
the EVP AEAD API using implementations EVP_aead_aes_128_ccm_bluetooth,
EVP_aead_aes_128_ccm_bluetooth_8, and EVP_aead_aes_128_ccm_matter
respectively.
Otherwise, there is no workaround and applications using aws-lc-sys should
upgrade to the most recent release.
{
"affected": [
{
"database_specific": {
"categories": [
"crypto-failure"
],
"cvss": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N",
"informational": null
},
"ecosystem_specific": {
"affected_functions": null,
"affects": {
"arch": [],
"functions": [],
"os": []
}
},
"package": {
"ecosystem": "crates.io",
"name": "aws-lc-sys",
"purl": "pkg:cargo/aws-lc-sys"
},
"ranges": [
{
"events": [
{
"introduced": "0.14.0"
},
{
"fixed": "0.38.0"
}
],
"type": "SEMVER"
}
],
"versions": []
}
],
"aliases": [
"CVE-2026-3337",
"GHSA-65p9-r9h6-22vj",
"GHSA-frmv-5gcm-jwxh"
],
"database_specific": {
"license": "CC0-1.0"
},
"details": "Observable timing discrepancy in AES-CCM decryption in AWS-LC allows an\nunauthenticated user to potentially determine authentication tag validity\nvia timing analysis.\n\nThe impacted implementations are through the EVP CIPHER API:\n`EVP_aes_128_ccm`, `EVP_aes_192_ccm`, and `EVP_aes_256_ccm`.\n\nCustomers of AWS services do not need to take action. `aws-lc-sys` contains\ncode from AWS-LC. Applications using `aws-lc-sys` should upgrade to the most\nrecent release of `aws-lc-sys`.\n\n## Workarounds\n\nIn the special cases of using AES-CCM with (M=4, L=2), (M=8, L=2), or\n(M=16, L=2), applications can workaround this issue by using AES-CCM through\nthe EVP AEAD API using implementations `EVP_aead_aes_128_ccm_bluetooth`,\n`EVP_aead_aes_128_ccm_bluetooth_8`, and `EVP_aead_aes_128_ccm_matter`\nrespectively.\n\nOtherwise, there is no workaround and applications using `aws-lc-sys` should\nupgrade to the most recent release.",
"id": "RUSTSEC-2026-0045",
"modified": "2026-03-21T06:45:35Z",
"published": "2026-03-02T12:00:00Z",
"references": [
{
"type": "PACKAGE",
"url": "https://crates.io/crates/aws-lc-sys"
},
{
"type": "ADVISORY",
"url": "https://rustsec.org/advisories/RUSTSEC-2026-0045.html"
},
{
"type": "WEB",
"url": "https://aws.amazon.com/security/security-bulletins/2026-005-AWS"
},
{
"type": "ADVISORY",
"url": "https://github.com/aws/aws-lc-rs/security/advisories/GHSA-65p9-r9h6-22vj"
}
],
"related": [],
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N",
"type": "CVSS_V3"
}
],
"summary": "Timing Side-Channel in AES-CCM Tag Verification in AWS-LC"
}
Sightings
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|---|
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