Liquid-co OpenSave: Path traversal enables arbitrary file read and write
Summary
OpenSave through version 2.4.0 does not properly validate save paths supplied by paired peers in the manifest and sync handlers. A peer can specify directories outside the configured save folders and read and write files there. According to a public write-up, the WAN relay sync path also does not authenticate the sender, so a user who only holds a room code may be able to register arbitrary directories on another machine. Confidentiality and integrity impact is high, and availability is not affected.
Affected
- OpenSave 0 up to and including 2.4.0 (per CVE record and VulnCheck)
- Default configuration is listed as unaffected by the CNA; exposure depends on paired peers and WAN/relay sync being enabled
Fixed in
- Unknown. No vendor advisory or confirmed fix found.
- v2.4.1 (released 02 Oct 2026) is not verified as a fix; check its changelog before deploying.
Workaround
- Disable WAN/relay sync until a fix is verified (recommendation, not a vendor workaround).
- Disable UPnP port forwarding (port 8386) on hosts that do not strictly need it.
- Pair only devices you own and remove unknown peers.
- Run OpenSave as a standard user and keep save folders separate from sensitive data.
Exploitation
- Not listed in CISA KEV. CISA SSVC: exploitation none, automatable no. EPSS below 1%.
- A public write-up exists; no working exploit code or public PoC was found.
- No known exploitation in the wild.
Our recommendation
- Check whether OpenSave is installed on company devices and confirm the installed version.
- Disable WAN/relay sync and UPnP port forwarding until a verified fix is installed.
- Pair only known devices and remove unknown peers.
- Verify the v2.4.1 changelog and vendor advisories before deploying any newer build.
- Monitor for vendor updates, as relevance is low for most SMEs unless staff use OpenSave on work devices.
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- VulnCheck advisory www.vulncheck.com
- Researcher write-up (Gist) gist.github.com
- OpenSave repository github.com
- OpenSave v2.4.0 release github.com
- OpenSave v2.4.1 release github.com
- OSV entry CVE-2026-103398 osv.dev
- OpenCVE CVE-2026-103398 app.opencve.io
- OpenSave README (UPnP option) github.com
Researched and written up in English and German by an AI (Claude by Anthropic) based on NVD, CISA, EPSS and the sources listed. The vendor information is authoritative. Researched on 1 Nov 2026, 09:34.
Original description (NVD)
OpenSave through 2.4.0 fails to properly validate save paths supplied by paired peers in the manifest request handler. Attackers can specify arbitrary directories outside configured save locations to read and write files through manifest and sync routes.
NVD references (5)
- https://gist.github.com/mansurmavlankulov/2ca66f95965fb9d4aab353bcf2434cdb
- https://github.com/Liquid-co/OpenSave
- https://github.com/Liquid-co/OpenSave/blob/v2.4.0/internal/delta/rootguard.go#L16-L30
- https://github.com/Liquid-co/OpenSave/blob/v2.4.0/internal/p2p/routes.go#L555-L566
- https://www.vulncheck.com/advisories/opensave-through-2.4.0-arbitrary-file-read-and-write-via-peer-controlled…
Sources
The tracker combines official, freely usable data sources – updated continuously:
- NVD (NIST) – CVEs, rating (CVSS), affected products
- CISA KEV – vulnerabilities confirmed by CISA as actively exploited
- CISA Vulnrichment – CISA assessment (SSVC) in the official CVE record
- FIRST EPSS – probability of exploitation
- Microsoft MSRC – Patch Tuesday: vulnerabilities, severity, updates
- PoC-in-GitHub – public proof-of-concept repositories
- Metasploit (Rapid7) – modules of the Metasploit Framework
- Exploit-DB (OffSec) – archive of public exploits (links only)
- Patch days: official vendor pages (linked per vendor) (Vendor patch days)
This product uses data from the NVD API but is not endorsed or certified by the NVD. EPSS data © FIRST.org.
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