CVE-2026-55168 Runtipi: Authenticated arbitrary file write via backup restore symlink planting
An authenticated attacker can exploit symlink handling in backup restore to write arbitrary files, potentially leading to code execution or privilege escalation.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-55168?
CVE-2026-55168 is a medium-severity path traversal vulnerability in runtipi, published on 21 Aug 2026. An attacker needs administrator access to exploit it, with no action from the victim.
Official description
Runtipi is a personal homeserver orchestrator. In 4.10.0 and earlier, Runtipi accepts symbolic links from an attacker-controlled backup archive and copies them into live application paths during the backup restore flow. An authenticated attacker can plant user-config/app.env as a symlink to an arbitrary reachable path and then send PUT /api/user-config/demoapp3:_user with attacker-controlled appEnv content. FilesystemService.writeTextFile() follows the planted link, allowing content to be written outside the intended restore and user-config directory boundary with Runtipi process permissions. This issue is fixed in version 4.10.1.
Which versions are affected by CVE-2026-55168?
How do I fix CVE-2026-55168?
No fix has been published for CVE-2026-55168 yet. Limit exposure of the affected software until one is available.
Upgrade, and resolve every user-supplied path against an allowed base folder before opening it. More about Path traversal.
Is CVE-2026-55168 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-55168 exists.
Public exploit code: 1 proofs of concept on GitHub.
Sources
Also known as GHSA-wcrf-g9p9-2wg7.