CVE-2021-21404 (GCVE-0-2021-21404)
Vulnerability from cvelistv5 – Published: 2021-04-06 20:00 – Updated: 2024-08-03 18:09
VLAI
EPSS
VEX
Title
Crash due to malformed relay protocol message
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.
Severity
7.5 (High)
CWE
- CWE-20 - Improper Input Validation
Assigner
GitHub_M
CNA
References
4 references
| URL | Tags |
|---|---|
| https://github.com/syncthing/syncthing/security/a… | x_refsource_CONFIRM |
| https://pkg.go.dev/github.com/syncthing/syncthing | x_refsource_MISC |
| https://github.com/syncthing/syncthing/commit/fb4… | x_refsource_MISC |
| https://github.com/syncthing/syncthing/releases/t… | x_refsource_MISC |
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The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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