# CVE-2026-100717: froxlor CRLF injection in subdomain redirect validation

Source: https://junglewise.ai/threats/cve-2026-100717-froxlor-is-a-server-administration-panel-in-versions-2-3-10-and  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-26. Updated: 2026-09-26  
License: CC BY 4.0 with a link back

CVE-2026-100717 · Severity: critical · CVSS 9.9 · Published 2026-09-26

froxlor is a server administration panel that manages web server configurations for hosting providers and resellers. A low-privilege customer with subdomain management rights can inject newline characters into server configuration files via a malicious subdomain redirect URL, allowing them to inject arbitrary nginx or Apache directives that take effect server-wide. This enables attackers to hijack web responses, read local files, or disable services on the server.

Technologies: [Froxlor](https://junglewise.ai/threats/technologies/froxlor). Vendors: [Froxlor](https://junglewise.ai/threats/vendors/froxlor).

## Quick answers

**Is CVE-2026-100717 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-100717 being exploited in the wild.

**How severe is CVE-2026-100717?** Critical severity, with a CVSS score of 9.9, published 26 September 2026.

**Which products and versions are affected?** Froxlor 2.3.10 and earlier.

**Is there a fix for CVE-2026-100717?** A patch was published on 2026-09-26: Fixed in version 2.3.12 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-100717 attacked?** It is attacked over the network.

**Am I affected by CVE-2026-100717?** Check whether you run Froxlor at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

The Validate::validateUrl function checks only the path, query, and fragment URL components for CRLF sequences but fails to inspect the userinfo (user:pass@) component returned by parse_url. An attacker supplies a subdomain redirect URL with newline characters encoded in the userinfo portion (e.g., http://user%0amalicious%0a@evil.com/), which passes validation and is written verbatim into the generated vhost configuration. When froxlor regenerates and reloads web server config as root, the injected directives execute with full privilege.

## Affected products

- froxlor froxlor 2.3.10 and earlier

## Timeline

- 2026-09-26: disclosed: Published as GHSA-gxx3-hwjc-h2gp
- 2026-09-26: patched: Fixed in version 2.3.12

## References

- [https://github.com/froxlor/froxlor/security/advisories/GHSA-gxx3-hwjc-h2gp](https://github.com/froxlor/froxlor/security/advisories/GHSA-gxx3-hwjc-h2gp)
- [https://www.vulncheck.com/advisories/froxlor-before-2.3.12-crlf-injection-via-validateurl-userinfo](https://www.vulncheck.com/advisories/froxlor-before-2.3.12-crlf-injection-via-validateurl-userinfo)

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