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.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Privileges Required
None
No privileges needed
User Interaction
Required
User action required
Impact Assessment
Confidentiality
Low
Partial data leak
Integrity
Low
Partial data modification
Availability
None
No disruption
CVSS Vector v3.1
Weakness Type (CWE)
Vulnerable Products 1
| Configuration | From (including) | Up to (excluding) |
|---|---|---|
|
Libops Captcha_Protect
cpe:2.3:a:libops:captcha_protect:*:*:*:*:*:traefik:*:*
|
— |
1.12.2
|
References 3
https://github.com/libops/captcha-protect/commit/eef6211ecd1147273be484d913b81c…
security-advisories@github.com
https://github.com/libops/captcha-protect/releases/tag/v1.12.2
security-advisories@github.com
https://github.com/libops/captcha-protect/security/advisories/GHSA-ph62-4j5g-2q…
security-advisories@github.com