CVE-2026-48105 Path traversal in arc
Attackers can exploit path traversal in Arc Enterprise cluster FSM to register arbitrary files, potentially enabling cluster-wide compromise or data access.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-48105?
CVE-2026-48105 is a high-severity path traversal vulnerability in Basekick-Labs arc, published on 21 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
Arc is an open, SQL-native time-series database for telemetry. Prior to version 26.06.1, Arc Enterprise's Raft FSM (`internal/cluster/raft/fsm.go:applyRegisterFile`) accepts attacker-chosen file paths in manifest-registration proposals without validating them against the configured storage backend. The only check is that the path is non-empty. There is no parent-traversal (`..`) rejection, no allowlist of legitimate prefixes, no scheme restriction (`s3://` vs local), and no length bound. This is fixed in 2026.06.1. Some workarounds are available. Restrict cluster network access to known-trusted peers via strict firewall rules, audit the cluster manifest for unexpected paths (any path not matching the configured storage backend root is suspect), and/or disable cluster mode until the fix is available.
Which versions are affected by CVE-2026-48105?
How do I fix CVE-2026-48105?
No fix has been published for CVE-2026-48105 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-2026-48105 being exploited?
There is no known exploitation of CVE-2026-48105 in the wild and no public exploit code.
Sources
Also known as GHSA-f85q-mvg8-qf37.