Vulnerability · Published Sep 26, 2026 · Assigned by VulnCheck

CVE-2026-100714Froxlor before 2.3.12 Command Injection via letsencryptchallengepath

Critical 9.1

In plain English

A critical-severity argument injection in froxlor from froxlor. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 46% of all known vulnerabilities).

Severity (CVSS 3.1)9.1Critical

Exploit odds (30 days)0.5%top 53.9% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

Froxlor before 2.3.12 does not restrict or escape the system.letsencryptchallengepath setting: unlike sibling settings hardened in GHSA-33mp, the field has no string_regexp or required_otp guard, and its value is concatenated unescaped into the acme.sh command line built in lib/Froxlor/Cron/Http/LetsEncrypt/AcmeSh.php and executed by the root cron via FileDir::safe_exec. Because safe_exec only blacklists shell metacharacters such as ; | & > < \ $ ~ ?, spaces and quotes survive and the value is word-split into additional acme.sh arguments. An administrator, or any actor able to write settings (for example through the settings-import API), can therefore inject acme.sh options such as --renew-hook, --pre-hook or --post-hook to obtain arbitrary command execution as root at the next Let's Encrypt cron run, or use --config-home/--cert-home for arbitrary file writes. Versions up to and including 2.3.10 are affected; the issue is fixed in 2.3.12.

Affected products (as reported)

Vendor	Product	Versions
froxlor	froxlor	0 – before 2.3.12

Weakness: CWE-88 · Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H

References

GitHub Security Advisory (GHSA-3w4g-cmpj-rj42) vendor-advisory
VulnCheck Advisory: Froxlor before 2.3.12 Command Injection via letsencryptchallengepath third-party-advisory