CVE-2026-3337
Timing Side-Channel in AES-CCM Tag Verification in AWS-LC
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- High
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
Timing Side-Channel in AES-CCM Tag Verification in AWS-LC
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.
- Record
CVE-2026-3337- CVSS 4.0
- 8.2 High
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 - CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N - Weakness
- CWE-208
- Updated
- 2026-11-02
EUVDEUVD-2026-9265
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.
- Record
EUVD-2026-9265- CVSS 4.0
- 8.2 High
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 - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-65p9-r9h6-22vj
AWS-LC has Timing Side-Channel in AES-CCM Tag Verification
Summary
AWS-LC is an open-source, general-purpose cryptographic library.
Impact
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. aws-lc-sys and aws-lc-fips-sys contain code from AWS-LC. Applications using aws-lc-sys or aws-lc-fips-sys should upgrade to the most recent releases of aws-lc-sys or aws-lc-fips-sys.
Impacted versions:
- aws-lc-sys versions: >= 0.14.0, < 0.38.0
- aws-lc-fips-sys versions: >= v0.13.0, < 0.13.12.
Patches
The patch is included in aws-lc-sys v.0.38.0 and aws-lc-fips-sys v0.13.12.
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 or aws-lc-fips-sys should upgrade to the most recent releases of aws-lc-sys or aws-lc-fips-sys.
Resources
If there are any questions or comments about this advisory, contact [AWS/Amazon] Security via thevulnerability reporting page or directly via email to [email protected]. Please do not create a public GitHub issue.
Acknowledgement
AWS-LC would like to thank Joshua Rogers (https://joshua.hu/) for collaborating on this issue through the coordinated vulnerability disclosure process.
- Record
GHSA-65p9-r9h6-22vj- CVSS 4.0
- 8.2 High
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 - CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N - Weakness
- CWE-208
- Updated
- 2026-11-02
NVD
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.
- Record
CVE-2026-3337- CVSS 4.0
- 8.2 High
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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N - Weakness
- CWE-208
- Updated
- 2026-11-02
OSV
Timing Side-Channel in AES-CCM Tag Verification in AWS-LC
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.
- Record
CVE-2026-3337- CVSS 4.0
- 8.2 High
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 - Weakness
- CWE-208
- Updated
- 2026-11-02
OSVGHSA-65p9-r9h6-22vj
AWS-LC has Timing Side-Channel in AES-CCM Tag Verification
Summary
AWS-LC is an open-source, general-purpose cryptographic library.
Impact
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. aws-lc-sys and aws-lc-fips-sys contain code from AWS-LC. Applications using aws-lc-sys or aws-lc-fips-sys should upgrade to the most recent releases of aws-lc-sys or aws-lc-fips-sys.
Impacted versions:
- aws-lc-sys versions: >= 0.14.0, < 0.38.0
- aws-lc-fips-sys versions: >= v0.13.0, < 0.13.12.
Patches
The patch is included in aws-lc-sys v.0.38.0 and aws-lc-fips-sys v0.13.12.
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 or aws-lc-fips-sys should upgrade to the most recent releases of aws-lc-sys or aws-lc-fips-sys.
Resources
If there are any questions or comments about this advisory, contact [AWS/Amazon] Security via thevulnerability reporting page or directly via email to [email protected]. Please do not create a public GitHub issue.
Acknowledgement
AWS-LC would like to thank Joshua Rogers (https://joshua.hu/) for collaborating on this issue through the coordinated vulnerability disclosure process.
- Record
GHSA-65p9-r9h6-22vj- CVSS 4.0
- 8.2 High
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 - CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N - Weakness
- CWE-208
- Updated
- 2026-11-02
OSVRUSTSEC-2026-0043
Timing Side-Channel in AES-CCM Tag Verification in AWS-LC
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. aws-lc-fips-sys
contains code from AWS-LC. Applications using aws-lc-fips-sys should
upgrade to the most recent release of aws-lc-fips-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-fips-sys
should upgrade to the most recent release of aws-lc-fips-sys.
- Record
RUSTSEC-2026-0043- CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N - Updated
- 2026-11-02
OSVRUSTSEC-2026-0045
Timing Side-Channel in AES-CCM Tag Verification in AWS-LC
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. 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.
- Record
RUSTSEC-2026-0045- CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N - Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
aws-lc-syscrates.io |
0.14.0 up to 0.38.0 | 0.38.0 |
aws-lc-fips-syscrates.io |
0.13.0 up to 0.13.12 | 0.13.12 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-3337 is a high vulnerability (CVSS 8.2) in Aws Aws-lc, published March 2, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.07%, the 65th percentile. Fixed in aws-lc-sys 0.38.0.
References
aws.amazon.com/security/security-bulletins/2026-005-AWS
github.com/aws/aws-lc/releases/tag/v1.69.0
nvd.nist.gov/vuln/detail/CVE-2026-3337
rustsec.org/advisories/RUSTSEC-2026-0043.html