CVE-2026-3338

PKCS7_verify Signature Validation Bypass in AWS-LC

CVSS 3.1 7.5 HIGHCVSS 4.0 8.7 HIGHEUVD CVSS 4.0 8.7 CVSS 4.0 · ff89ba41-3aa1-4d27-914a-91399e9639e5 · Secondary 8.7 HIGHCVSS 3.1 · ff89ba41-3aa1-4d27-914a-91399e9639e5 · Secondary 7.5 HIGHCVSS 3.1 · 0b0ca135-0b70-47e7-9f44-1890c2a1c46c · Secondary 7.5 HIGHCVSS_V3 Publisher rating HIGHFixed by aws-lc-sys 0.38.0CVSS_V3 Fixed by aws-lc-sys 0.38.0KEV status unknown

Original advisory

cve-program · CVE-2026-3338

Published

Improper signature validation in PKCS7_verify() in AWS-LC allows an unauthenticated user to bypass signature verification when processing PKCS7 objects with Authenticated Attributes. Customers of AWS services do not need to take action. Applications using AWS-LC should upgrade to AWS-LC version 1.69.0.

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euvd · EUVD-2026-9266

Published

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nvd · CVE-2026-3338

Published

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osv · GHSA-hfpc-8r3f-gw53

Published

### Summary AWS-LC is an open-source, general-purpose cryptographic library. ### Impact Improper signature validation in PKCS7_verify() in AWS-LC allows an unauthenticated user to bypass signature verification when processing PKCS7 objects with Authenticated Attributes. 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. #### Impacted versions: aws-lc-sys versions: >= 0.24.0, < 0.38.0 ### Patches The patch is included in v0.38.0 ### Workarounds There is no workaround. Applications using aws-lc-sys should upgrade to the most recent release of aws-lc-sys. ### Resources If there are any questions or comments about this advisory, contact [AWS/Amazon] Security via the [vulnerability reporting page](https://aws.amazon.com/security/vulnerability-reporting) or directly via email to [[email protected]](mailto:[email protected]). Please do not create a public GitHub issue.

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osv · RUSTSEC-2026-0047

Published

Improper signature validation in `PKCS7_verify()` in AWS-LC allows an unauthenticated user to bypass signature verification when processing PKCS7 objects with Authenticated Attributes. 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`. There is no workaround; applications using `aws-lc-sys` should upgrade to the most recent release of `aws-lc-sys`.

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Affected versions, risk and source history

Exploitation and risk

Source status

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Risk history

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Advisory history

15 saved versions

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15 Nov 2026 10:03:09 UTC