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Medium 6.1

Cross-Site Scripting (XSS) in Captcha Protect

CVE-2026-34206 First seen on SecPulse

Summary

Cross-site scripting in Captcha Protect (CVE-2026-34206). Risk of unauthorized operations or information disclosure.

Auto-generated summary

Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.

A vulnerability tracked as CVE-2026-34206 has been found in Captcha Protect.
Risk of unauthorized operations or information disclosure. CVSS score: 6.1/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Captcha Protect CVE-2026-34206" on the vendor's site.

CVE-2026-34206 (Captcha Protect) — CWE-79 / CVSS v3 6.1
Attack vector: remote (network-reachable) / unauthenticated
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.

What is the problem

Cross-site scripting (XSS) (CWE-79) exists in Captcha Protect.

Affected scope

Check the vendor advisory for the affected versions of Captcha Protect.

Severity

Severity: Medium (CVSS 6.1/10). Risk of unauthorized operations or information disclosure.

How to fix

Update to the patched release per vendor advisory.

Workaround

Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.

Detection

Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Audit SBOM/dependencies to find affected services.

Response actions

Concrete steps and command examples for SOC/SRE teams to execute in order

  1. 1
    Identify exposureidentify
    Audit SBOM/dependencies for affected components.

    資産台帳・SBOM・依存マニフェストで Captcha Protect を使っているサービスとバージョンを洗い出す。

  2. 2
    Post-deployment verificationverify
    Confirm patched version is live in production

    パッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。

Original description The description as published by the source.

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.

Source: NIST National Vulnerability Database NVD GitHub Advisory

References

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