CVE-2026-113667 apostrophecms CVE debrief

Who should care

Defenders responsible for ApostropheCMS deployments, specifically those using @apostrophecms/form, @apostrophecms/login-recaptcha, and @apostrophecms/login-hcaptcha packages, should assess exposure and prioritize verification and updates.

Why it matters

Defenders should prioritize verifying and updating affected packages to prevent potential verification failures and automated bypass probing.

• Verification failures due to injected query parameters
• Potential automated bypass probing
• Denial of Service (DoS) of CAPTCHA gate and CAPTCHA-gated login/form flows

Technical summary

The vulnerability is caused by the lack of URL encoding for user-supplied CAPTCHA response tokens in the server-side verification URL/body. This allows an attacker to inject extra key-value pairs into the outbound verify call, forcing verification failures and enabling automated bypass probing. The affected code is located in packages/form/lib/recaptcha.js:39, packages/login-recaptcha/index.js:44, and packages/login-hcaptcha/index.js:47. The vulnerability has a low impact, allowing for denial of service (DoS) of the CAPTCHA gate and CAPTCHA-gated login/form flows, but does not enable secret exfiltration.

Defensive priority

Defenders should prioritize verifying and updating @apostrophecms/form, @apostrophecms/login-recaptcha, and @apostrophecms/login-hcaptcha packages to the fixed versions.

Recommended defensive actions

• Verify and update @apostrophecms/form to version 1.5.5 or later
• Verify and update @apostrophecms/login-recaptcha to version 1.2.1 or later
• Verify and update @apostrophecms/login-hcaptcha to version 1.3.0 or later
• Review and adjust CAPTCHA implementation to ensure proper encoding of user-supplied tokens
• 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

Evidence notes

The vulnerability is caused by the lack of URL encoding for user-supplied CAPTCHA response tokens in the server-side verification URL/body. This allows an attacker to inject extra key-value pairs into the outbound verify call, forcing verification failures and enabling automated bypass probing.

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.