CVE-2021-21404 (GCVE-0-2021-21404)
Vulnerability from cvelistv5
Published
2021-04-06 20:00
Modified
2024-08-03 18:09
Severity ?
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE
  • CWE-20 - Improper Input Validation
Summary
Syncthing is a continuous file synchronization program. In Syncthing before version 1.15.0, the relay server `strelaysrv` can be caused to crash and exit by sending a relay message with a negative length field. Similarly, Syncthing itself can crash for the same reason if given a malformed message from a malicious relay server when attempting to join the relay. Relay joins are essentially random (from a subset of low latency relays) and Syncthing will by default restart when crashing, at which point it's likely to pick another non-malicious relay. This flaw is fixed in version 1.15.0.
References
security-advisories@github.comhttps://github.com/syncthing/syncthing/commit/fb4fdaf4c0a79c22cad000c42ac1394e3ccb6a97Patch, Third Party Advisory
security-advisories@github.comhttps://github.com/syncthing/syncthing/releases/tag/v1.15.0Release Notes, Third Party Advisory
security-advisories@github.comhttps://github.com/syncthing/syncthing/security/advisories/GHSA-x462-89pf-6r5hThird Party Advisory
security-advisories@github.comhttps://pkg.go.dev/github.com/syncthing/syncthingProduct, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://github.com/syncthing/syncthing/commit/fb4fdaf4c0a79c22cad000c42ac1394e3ccb6a97Patch, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://github.com/syncthing/syncthing/releases/tag/v1.15.0Release Notes, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://github.com/syncthing/syncthing/security/advisories/GHSA-x462-89pf-6r5hThird Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://pkg.go.dev/github.com/syncthing/syncthingProduct, Third Party Advisory
Impacted products
Vendor Product Version
syncthing syncthing Version: < 1.15.0
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