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

Read the publisher's advisory

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

cve-program · CVE-2026-3338

Published

AWS-LC

Vendor product

Publisher's version information

Shown as published. These rules are not interpreted as NuGet package version ranges.

{
                    "defaultStatus": "unaffected",
                    "product": "AWS-LC",
                    "vendor": "AWS",
                    "versions": [
                        {
                            "lessThan": "1.69.0",
                            "status": "affected",
                            "version": "1.41.0",
                            "versionType": "custom"
                        }
                    ]
                }

Original source record · Cite this exact observation · Complete original publisher JSON

euvd · EUVD-2026-9266

Published

EUVD source date text has no stated timezone and is retained without inventing a UTC instant. Related bulletin membership is not an alias, common cause or applicability claim. A missing vector with a zero score is treated as unrated. Complete vendor/product and underlying source evidence remains in the original JSON.

Original publisher date fields

datePublished: Mar 2, 2026, 9:22:41 PM

dateUpdated: Aug 21, 2026, 12:12:53 PM

2 related source bulletins · separate from aliases

msrc_CVE-2026-3338: PKCS7_verify Signature Validation Bypass in AWS-LC

CVE-2026-3338

RHSA-2026:5459: Red Hat Security Advisory: RHTAS 1.3.3 - Red Hat Trusted Artifact Signer Release

CVE-2025-66471 · CVE-2026-3336 · CVE-2026-3338 · CVE-2026-21441 · CVE-2026-31812

No normalized affected-package data is projected for this source revision. The original publisher record may contain additional product and version evidence; this does not establish that a package is unaffected.

Original source record · Cite this exact observation · Complete original publisher JSON

nvd · CVE-2026-3338

Published

NVD analysis and CPE criteria are source context, not proof that a package or your environment is affected. Complete affected data, logical configurations and SSVC are retained in the original JSON.

Source analysis status: Modified

Weakness classifications: CWE-347

Original publisher date fields

published: 2026-03-02T22:16:32.350

lastModified: 2026-07-15T02:20:59.787

2 source CPE criteria · context only

cpe:2.3:a:amazon:aws-lc-sys:*:*:*:*:*:rust:*:*
cpe:2.3:a:amazon:aws_libcrypto:*:*:*:*:*:*:*:*

The original JSON retains the logical configuration operators, exclusions and version bounds.

Original source record · Cite this exact observation · Complete original publisher JSON

osv · GHSA-hfpc-8r3f-gw53

Published

aws-lc-sys

crates.io

SEMVER · introduced 0.24.0 → fixed 0.38.0

Original source record · Cite this exact observation · Complete original publisher JSON

osv · RUSTSEC-2026-0047

Published

aws-lc-sys

crates.io

SEMVER · introduced 0.24.0 → fixed 0.38.0

Original source record · Cite this exact observation · Complete original publisher JSON