CVE-2026-34206

MEDIUM

Captcha Protect: Reflected XSS in challenge page via unsanitized destination rendered with text/template

Title source: cna

Description

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.

Scores

CVSS v3 6.1
EPSS 0.0004
EPSS Percentile 11.1%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact partial

Details

CWE
CWE-79
Status published
Products (2)
libops/captcha-protect < 1.12.2
libops/captcha_protect < 1.12.2
Published Mar 31, 2026
Tracked Since Apr 01, 2026