Aws Lc SysApplication · Amazon
CVE-2026-3338
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedImproper 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.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · high confidenceImproper signature validation in AWS-LC's PKCS7_verify() function allows unauthenticated attackers to bypass signature verification when processing PKCS7 objects containing Authenticated Attributes. This cryptographic validation flaw enables attackers to forge signed PKCS7 messages that appear valid.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data
Aws Lc SysApplication
>= 0.24.0, < 0.38.0>= 1.41.0, < 1.69.0CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Network
- Complexity
- Low
- Privileges
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- High
- Availability
- None
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
-
Identify installed AWS-LC library versionLocate the aws-lc-sys or aws-libcrypto library binary or header file and read its version metadata. Common locations include /usr/lib/, /usr/local/lib/, or application-bundled lib directories. Use commands like 'strings libaws-lc.a | grep -i version' or check the library filename for version strings.Affected if The version is >= 0.24.0 and < 0.38.0 for aws-lc-sys, or >= 1.41.0 and < 1.69.0 for aws-libcrypto
-
Determine if PKCS7_verify function is usedSearch application source code for calls to PKCS7_verify, PKCS7_signatureVerify, or similar PKCS7 signature verification functions. Use 'grep -r "PKCS7_verify"' or examine linked symbols in the application binary with 'nm' or 'ldd'.Affected if The application links against a vulnerable AWS-LC version AND calls PKCS7_verify or related functions to verify signatures on PKCS7 data
-
Check if Authenticated Attributes are processedReview the PKCS7 data flow in the application to determine whether signed PKCS7 objects contain Authenticated Attributes (OID 1.2.840.113549.1.9.16.2). Inspect any PKCS7 parsing or verification logic to see if authenticated attribute handling is involved.Affected if PKCS7 data containing Authenticated Attributes is being validated using the vulnerable verification function
You are affected if your application uses a vulnerable AWS-LC library version and performs PKCS7 signature verification on PKCS7 objects with Authenticated Attributes.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
dbcve · scoped0.38.01.69.0
Upgrade AWS-LC library to version 1.69.0 or later in all applications that use this library. No action required for AWS service customers directly.
AWS-LC version 1.69.0
- Identify the current AWS-LC version in use by checking project dependencies or libraries
- Update the AWS-LC dependency to version 1.69.0 or later in your build configuration (e.g., package.json, Cargo.toml, requirements.txt, or build system)
- Rebuild and recompile the application to link against the new AWS-LC version
- Verify the PKCS7_verify() functionality works correctly in your application
- Run existing test suites to ensure no regressions were introduced
Generated from the published advisory — verify against the referenced sources before acting.
Fix this in Aws Lc Sys
Scoped from the published advisory
- Consultation2.0 h
- Implementation2.0 h
- Testing4.0 h
- Review / QA2.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,752.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2026-3338 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2026-3338 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.
A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.
- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
- No weaponised exploit code, or anything meant to cause harm
- No spam, self-promotion, credentials, or personal data