CVE-2026-3336: CWE-295 (Improper Certificate Validation) in AWS AWS-LC
CVE-2026-3336 is a high-severity vulnerability in AWS-LC affecting the PKCS7_verify() function. It allows an unauthenticated user to bypass certificate chain verification when processing PKCS7 objects that have multiple signers, except for the final signer. This improper certificate validation could lead to integrity issues in verifying signed data. AWS customers using AWS services are not required to take any action. Applications that use AWS-LC directly should upgrade to version 1. 69. 0 to remediate this issue.
AI Analysis
Technical Summary
This vulnerability (CVE-2026-3336) in AWS-LC arises from improper certificate validation in the PKCS7_verify() function. Specifically, when processing PKCS7 objects with multiple signers, the verification process bypasses certificate chain validation for all but the final signer. This flaw could allow an unauthenticated attacker to cause the application to accept invalid or maliciously crafted signed data. The issue is tracked under CWE-295 (Improper Certificate Validation) and has a CVSS 3.1 base score of 7.5, indicating high severity. AWS has indicated that customers of AWS cloud services do not need to take action, implying the vulnerability does not affect managed cloud services. However, applications that embed AWS-LC must upgrade to version 1.69.0 to fix the vulnerability.
Potential Impact
The vulnerability allows an unauthenticated attacker to bypass certificate chain verification for multiple signers in PKCS7 objects, potentially leading to acceptance of forged or tampered signed data. This compromises the integrity of signature validation but does not affect confidentiality or availability. The impact is limited to applications using the vulnerable AWS-LC library version 1.41.0 or similar versions prior to 1.69.0. AWS cloud service customers are not impacted and require no action.
Mitigation Recommendations
Applications using AWS-LC should upgrade to version 1.69.0, which contains the official fix for this vulnerability. Customers using AWS cloud services do not need to take any action as the vendor manages remediation for those environments. Patch status is confirmed by the vendor advisory stating upgrade to AWS-LC 1.69.0 is required for remediation.
CVE-2026-3336: CWE-295 (Improper Certificate Validation) in AWS AWS-LC
Description
CVE-2026-3336 is a high-severity vulnerability in AWS-LC affecting the PKCS7_verify() function. It allows an unauthenticated user to bypass certificate chain verification when processing PKCS7 objects that have multiple signers, except for the final signer. This improper certificate validation could lead to integrity issues in verifying signed data. AWS customers using AWS services are not required to take any action. Applications that use AWS-LC directly should upgrade to version 1. 69. 0 to remediate this issue.
CVSS v3.1
Score 7.5high
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CVE-2026-3336) in AWS-LC arises from improper certificate validation in the PKCS7_verify() function. Specifically, when processing PKCS7 objects with multiple signers, the verification process bypasses certificate chain validation for all but the final signer. This flaw could allow an unauthenticated attacker to cause the application to accept invalid or maliciously crafted signed data. The issue is tracked under CWE-295 (Improper Certificate Validation) and has a CVSS 3.1 base score of 7.5, indicating high severity. AWS has indicated that customers of AWS cloud services do not need to take action, implying the vulnerability does not affect managed cloud services. However, applications that embed AWS-LC must upgrade to version 1.69.0 to fix the vulnerability.
Potential Impact
The vulnerability allows an unauthenticated attacker to bypass certificate chain verification for multiple signers in PKCS7 objects, potentially leading to acceptance of forged or tampered signed data. This compromises the integrity of signature validation but does not affect confidentiality or availability. The impact is limited to applications using the vulnerable AWS-LC library version 1.41.0 or similar versions prior to 1.69.0. AWS cloud service customers are not impacted and require no action.
Mitigation Recommendations
Applications using AWS-LC should upgrade to version 1.69.0, which contains the official fix for this vulnerability. Customers using AWS cloud services do not need to take any action as the vendor manages remediation for those environments. Patch status is confirmed by the vendor advisory stating upgrade to AWS-LC 1.69.0 is required for remediation.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- AMZN
- Date Reserved
- 2026-02-27T15:16:27.359Z
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 69a60221d1a09e29cb4eac7d
Added to database: 3/2/2026, 9:33:21 PM
Last enriched: 5/26/2026, 8:31:32 PM
Last updated: 5/31/2026, 1:10:32 AM
Views: 182
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