CVE-2026-77634 cakephp CVE debrief

Who should care

Defenders responsible for maintaining and securing PHP applications using CakePHP should assess exposure and prioritize upgrading to the fixed versions. This includes operators, platform administrators, vulnerability management teams, and security teams who need to review and update code to ensure proper handling of user-controlled data in message headers. They should also monitor for potential header injection attacks and review compensating controls for

Why it matters

Defenders should prioritize upgrading to the fixed versions of CakePHP to prevent potential header injection attacks. This vulnerability allows for header injection when user-controlled data is used in message headers, and the fixed versions ensure proper handling of such data.

• Potential for header injection attacks
• Need to upgrade to fixed versions to prevent vulnerability exploitation
• Importance of proper handling of user-controlled data in message headers

Technical summary

The vulnerability in CakePHP allows for header injection when user-controlled data is used in message headers. This is due to custom mail headers added with Message::setHeaders() or Message::addHeaders() not having CRLF bytes removed. The fixed versions ensure proper handling of such data, preventing potential header injection attacks. Affected product context indicates CakePHP versions prior to 4.5.12, 4.6.5, 5.1.8, 5.2.14, and 5.3.7 are vulnerable. Defenders should prioritize upgrading to the fixed versions to prevent potential header injection attacks.

Defensive priority

Defenders should prioritize upgrading to the fixed versions of CakePHP to prevent potential header injection attacks.

Recommended defensive actions

• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up.
• Review the supplied official advisory or CVE record to validate affected scope, severity, and vendor guidance.
• Plan vendor-supported updates or mitigations through normal change control where exposure is confirmed.
• Review compensating controls for exposed systems while remediation is scheduled and verified.
• Check 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.
• Upgrade to CakePHP version 4.5.12, 4.6.5, 5.1.8, 5.2.14, or 5.3.7

Evidence notes

The CVE record and NVD vulnerability detail page provide information on the vulnerability, its impact, and the fixed versions. Defenders should verify the affected scope, severity, and vendor guidance. The vulnerability allows for header injection when user-controlled data is used in message headers, and the fixed versions ensure proper handling of such data. Evidence limits and source grounding indicate potential exposure in managed environments.

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.