Improper Input Validation Affecting syncthing package, versions <1.15.1-r0


Severity

Recommended
0.0
high
0
10

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Threat Intelligence

EPSS
0.24% (62nd percentile)

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  • Snyk IDSNYK-ALPINE321-SYNCTHING-8489596
  • published6 Dec 2024
  • disclosed6 Apr 2021

Introduced: 6 Apr 2021

CVE-2021-21404  (opens in a new tab)
CWE-20  (opens in a new tab)

How to fix?

Upgrade Alpine:3.21 syncthing to version 1.15.1-r0 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream syncthing package and not the syncthing package as distributed by Alpine. See How to fix? for Alpine:3.21 relevant fixed versions and status.

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.

CVSS Scores

version 3.1