Froxlor before 2.3.12 Privilege Escalation via SSH Key Sync
Key facts
- Attack vector
- Network
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- —
- Confidentiality · integrity · availability
- High · None · None
- Fix status
- Fixed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA.
Summary
Froxlor 2.3.10 and earlier contain a time-of-check time-of-use (TOCTOU) race condition in the SSH key synchronization cron (lib/Froxlor/Cron/System/SshKeys.php, SshKeys::generateFiles). The containment/symlink validation performed by FileDir::makeCorrectDir()/makeCorrectFile() is done only at check time; the live filesystem path is re-resolved as root at write time (file_put_contents with FILE_APPEND|LOCK_EX, followed by chmod/chown/chgrp), with a database round-trip and file reads in between, and no path or file-descriptor pinning (no O_NOFOLLOW or openat2(RESOLVE_NO_SYMLINKS)). On installations where the non-default setting system.allow_customer_shell=1 grants customers local shell access, a customer can atomically swap their ~/.ssh directory for a symlink after the check and before the write, causing the root-run cron to append the customer's public key to /root/.ssh/authorized_keys and to chown /root/.ssh to the customer, resulting in full root compromise of the panel host. The cron re-runs on every interval, allowing unlimited attempts. This is a residual race that bypasses the check-time fix introduced for GHSA-mq5v-... . The issue is fixed in Froxlor 2.3.12.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Total
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
Remediation
- Fix · CNA froxlor (froxlor) Fixed in 2.3.12
Fixed in the same release
Records fixed by the same vendor advisory or release, as the CNA lists them.
- Release ·
froxlor 2.3.12
11 records Highest priority Priority HIGH 3 HIGH, 3 MEDIUM, 5 LOW
Other records, highest priority first
- TI-2026-64867 froxlor before 2.3.12 Authentication Bypass via Session PersistencePriority HIGH 77
- TI-2026-64872 Froxlor before 2.3.12 Privilege Escalation via SymlinkPriority HIGH 76
- TI-2026-64871 Froxlor before 2.3.12 Arbitrary File Deletion via SymlinkPriority HIGH 72
Timeline
- 2026-10-02 Threatist record created from CVE-2026-100713
- 2026-10-03 Alias added: GHSA-cvg5-3xjx-32m5
References
More froxlor vulnerabilities
- TI-2023-00300 Command Injection in froxlor/froxlor CVSS 3.1HIGH 8.8
- TI-2023-02973 Improper Restriction of Excessive Authentication Attempts in froxlor/froxlor CVSS 3.1CRITICAL 9.8
- TI-2023-01234 Authentication Bypass by Primary Weakness in froxlor/froxlor CVSS 3.1CRITICAL 9.8
- TI-2023-01911 Unrestricted Upload of File with Dangerous Type in froxlor/froxlor CVSS 3.1HIGH 8.8
- TI-2026-64867 froxlor before 2.3.12 Authentication Bypass via Session Persistence CVSS 4.0HIGH 8.7
- TI-2026-76945 Symlink following in Froxlor enables root privilege escalation CVSS 4.0CRITICAL 9.4
Sources
- CVE-2026-100713 · CVE Program
- CVE-2026-100713 · NVD
- FIRST EPSS
- GHSA-cvg5-3xjx-32m5 · GitHub Advisory Database · CC BY 4.0
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