CVE-2026-100714
Froxlor before 2.3.12 Command Injection via letsencryptchallengepath
CVE-2026-100714 is a critical vulnerability (CVSS 9.4) in Froxlor, published September 26, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.55%, the 45th percentile. No source names a fixed version.
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- High
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
9.4
Froxlor before 2.3.12 Command Injection via letsencryptchallengepath
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.
- Record
CVE-2026-100714- CVSS 4.0
- 9.4 Critical
CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H - CVSS 3.1
- 9.1 Critical
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H - Weakness
- CWE-88
- Updated
- 2026-11-02
EUVDEUVD-2026-87687
9.4
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.
- Record
EUVD-2026-87687- CVSS 4.0
- 9.4 Critical
CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-fh3h-q9pj-x5qp
9.4
Froxlor before 2.3.12 does not restrict or escape the system.letsencryptchallengepath setting:...
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.
- Record
GHSA-fh3h-q9pj-x5qp- CVSS 4.0
- 9.4 Critical
CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 9.1 Critical
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H - Weakness
- CWE-88
- Updated
- 2026-11-02
NVD
9.4
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.
- Record
CVE-2026-100714- CVSS 4.0
- 9.4 Critical
CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 9.1 Critical
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H - Weakness
- CWE-88
- Updated
- 2026-11-02
OSV
9.4
Froxlor before 2.3.12 Command Injection via letsencryptchallengepath
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.
- Record
CVE-2026-100714- CVSS 4.0
- 9.4 Critical
CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H - Weakness
- CWE-88
- Updated
- 2026-11-02
Affected products
History
| When | Changed | Sources |
|---|---|---|
| 2026-11-02 | created | CVE List, EUVD, GitHub Advisories, NVD, OSV |
References
github.com/froxlor/froxlor/security/advisories/GHSA-3w4g-cmpj-rj42
vulncheck.com/advisories/froxlor-before-2.3.12-command-injection-via-letsencryptchallengepath
nvd.nist.gov/vuln/detail/CVE-2026-100714
github.com/advisories/GHSA-fh3h-q9pj-x5qp
github.com/CVEProject/cvelistV5/tree/main/cves/2026/100xxx/CVE-2026-100714.json