Get a Demo

Let's Patch It!

Book a short call with one our specialists, we'll walk you through how Endor Patches work, and ask you a few questions about your environment (like your primary programming languages and repository management). We'll also send you an email right after you fill out the form, feel free to reply with any questions you have in advance!

CVE

CVE-2026-3336

AWS-LC has PKCS7_verify Certificate Chain Validation Bypass
Back to all
CVE

CVE-2026-3336

AWS-LC has PKCS7_verify Certificate Chain Validation Bypass

Summary

AWS-LC is an open-source, general-purpose cryptographic library.

Impact

Improper certificate validation in PKCS7_verify() in AWS-LC allows an unauthenticated user to bypass certificate chain verification when processing PKCS7 objects with multiple signers, except the final signer.

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 or directly via email to aws-security@amazon.com. 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.

Package Versions Affected

Package Version
patch Availability
No items found.

Automatically patch vulnerabilities without upgrading

Fix Without Upgrading
Detect compatible fix
Apply safe remediation
Fix with a single pull request

CVSS Version

Severity
Base Score
CVSS Version
Score Vector
C
H
U
8.7
-
4.0
CVSS:4.0/AV:N/AC:L/AT:N/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
C
H
U
0
-
3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
C
H
U
-

Related Resources

No items found.

References

https://github.com/aws/aws-lc-rs/security/advisories/GHSA-vw5v-4f2q-w9xf, https://github.com/aws/aws-lc/security/advisories/GHSA-cfwj-9wp5-wqvp, https://nvd.nist.gov/vuln/detail/CVE-2026-3336, https://aws.amazon.com/security/security-bulletins/2026-005-AWS, https://github.com/aws/aws-lc-rs, https://rustsec.org/advisories/RUSTSEC-2026-0046.html

Severity

7.5

CVSS Score
0
10

Basic Information

Ecosystem
Base CVSS
7.5
EPSS Probability
0.00015%
EPSS Percentile
0.03064%
Introduced Version
0.24.0,0
Fix Available
0.38.0,20260311-r0,0.22.1-r2,2.7.5-r0,2.4.2-r2,1.19.5-r4,0.1.9-r0,0.1.7-r0,26.3.2-r0,1.6.6-r2,2.342.0-r1,0.23.0-r1,1.7.1-r1,0.111.0-r3,2.5.14-r1,0.65.0-r1,0.15.0-r5,1.28.2-r5,0.10.8-r0,0.227.1-r1,0.44.0-r0,1.23.1-r1,1.27.8-r1,1.28.5-r1,1.29.1-r1

Fix Critical Vulnerabilities Instantly

Secure your app without upgrading.
Fix Without Upgrading