CVE-2026-74901 jahlives CVE debrief

Who should care

Users and administrators of openssl_encrypt versions before 1.4.0 should verify and update to version 1.4.0 or later to prevent authentication bypass attacks. This includes operators, platform administrators, vulnerability management teams, and security teams responsible for maintaining and securing systems that utilize openssl_encrypt. Additionally, security teams should review the official advisory and CVE record to assess the potential impact on their organization and plan accordingly.

Technical summary

openssl_encrypt versions before 1.4.0 contain an authentication bypass vulnerability in pqc.py where AES-GCM decryption failures trigger fallback to unauthenticated AES-CTR mode; attackers can modify ciphertext in transit to bypass integrity verification and perform bit-flipping attacks without detection. The vulnerability has been identified in the pqc.py file, which may be present in various product deployments.

Defensive priority

openssl_encrypt versions before 1.4.0 contain an authentication bypass vulnerability; verify and update to version 1.4.0 or later.

Recommended defensive actions

• Verify openssl_encrypt version and update to 1.4.0 or later
• Review and validate the usage of pqc.py and AES-GCM decryption
• Implement compensating controls to detect and prevent bit-flipping attacks
• Review relevant monitoring, detection, and logs for exposed assets that need extra review
• Track exceptions, retest remediated assets, and close the item only after evidence is documented
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up
• Plan vendor-supported updates or mitigations through normal change control where exposure is confirmed

Evidence notes

The vulnerability exists in pqc.py where AES-GCM decryption failures trigger fallback to unauthenticated AES-CTR mode; verify the presence of this file and its usage. Evidence limits suggest that additional verification tasks may be required to confirm affected scope and impact. Defenders should review the official advisory and CVE record for further details.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.