CVE-2021-21404

Summary

CVECVE-2021-21404
StatePUBLIC
Assigner[email protected]
Source PriorityCVE Program / NVD first with legacy fallback
Published2021-04-06 20:15:00 UTC
Updated2021-04-14 18:00:00 UTC
DescriptionSyncthing 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.

Risk And Classification

Problem Types: CWE-20

NVD Known Affected Configurations (CPE 2.3)

TypeVendorProductVersionUpdateEditionLanguage
Application Syncthing Syncthing All All All All

References

ReferenceSourceLinkTags
Release v1.15.0 · syncthing/syncthing · GitHub MISC github.com
syncthing · pkg.go.dev MISC pkg.go.dev
Merge pull request from GHSA-x462-89pf-6r5h · syncthing/syncthing@fb4fdaf · GitHub MISC github.com
Crash due to malformed relay protocol message · Advisory · syncthing/syncthing · GitHub CONFIRM github.com
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

Legacy QID Mappings

  • 180256 Debian Security Update for syncthing (CVE-2021-21404)
  • 501696 Alpine Linux Security Update for syncthing
  • 501928 Alpine Linux Security Update for syncthing
  • 690173 Free Berkeley Software Distribution (FreeBSD) Security Update for syncthing (9ee01e60-6045-43df-98e5-a794007e54ef)
  • 750224 OpenSUSE Security Update for syncthing (openSUSE-SU-2021:0688-1)
  • 982429 Go (go) Security Update for github.com/syncthing/syncthing (GHSA-x462-89pf-6r5h)

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