CVE-2026-34206: Libops Captcha Protect

Medium severity, CVSS 6.1. EPSS: 0.3% chance of exploitation in the next 30 days.

Captcha Protect is a Traefik middleware to add an anti-bot challenge to individual IPs in a subnet when traffic spikes are detected from that subnet. Prior to version 1.12.2, a reflected cross-site scripting (XSS) vulnerability exists in github.com/libops/captcha-protect. The challenge page accepted a client-supplied destination value and rendered it into HTML using Go's text/template. Because text/template does not perform contextual HTML escaping, an attacker could supply a crafted destination value that breaks out of the hidden input attribute and injects arbitrary script into the challenge page. This issue has been patched in version 1.12.2.

Affected products

• Libops Captcha Protect: before 1.12.2 (fixed in 1.12.2)

Published 2026-03-31. Last modified 2026-07-24.