CVE-2026-100717 froxlor before 2.3.12 CRLF Injection via validateUrl userinfo
Authenticated users can inject CRLF characters into subdomain URLs to modify web server configurations, potentially leading to code execution or data exposure.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-100717?
CVE-2026-100717 is a high-severity vulnerability in froxlor, published on 26 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
froxlor is a server administration panel. In versions 2.3.10 and earlier, Validate::validateUrl rejects carriage return and line feed characters only in the path, query and fragment components returned by parse_url, and never inspects the userinfo (user:pass@) components. This is an incomplete fix for GHSA-c3p2. An authenticated low-privilege customer with subdomain-create rights (no admin or change_serversettings privilege required) can supply a subdomain redirect URL that carries a CR/LF payload in the userinfo portion (e.g. http://user%0areturn 200 "pwned";%[email protected]/). The value passes validation, survives IDNA encoding, and is written verbatim into the generated nginx or Apache vhost configuration, allowing the attacker to break out of the emitted directive and inject arbitrary web-server configuration lines. froxlor regenerates and reloads the web-server configuration as root, so the injected directives take effect server-wide and can hijack responses or read local files. The issue is fixed in version 2.3.12.
Weakness: CWE-93
Which versions are affected by CVE-2026-100717?
How do I fix CVE-2026-100717?
No fix has been published for CVE-2026-100717 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-100717 being exploited?
There is no known exploitation of CVE-2026-100717 in the wild and no public exploit code.
Sources
Also known as GHSA-gxx3-hwjc-h2gp, GHSA-qjpj-j6j4-mcpf.