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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities
NOTICE UPDATE

NIST has updated the NVD program announcement page with additional information regarding recent concerns and the temporary delays in enrichment efforts.

CVE-2021-21404 Detail

Description

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

 


CVSS 3.x Severity and Metrics:

NIST CVSS score matches with CNA score
CNA:  GitHub, Inc.
Base Score:  7.5 HIGH
Vector:  CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H


NVD Analysts use publicly available information to associate vector strings and CVSS scores. We also display any CVSS information provided within the CVE List from the CNA.

Note: The NVD and the CNA have provided the same score. When this occurs only the CNA information is displayed, but the Acceptance Level icon for the CNA is given a checkmark to signify NVD concurrence.

References to Advisories, Solutions, and Tools

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Hyperlink Resource
https://github.com/syncthing/syncthing/commit/fb4fdaf4c0a79c22cad000c42ac1394e3ccb6a97 Patch  Third Party Advisory 
https://github.com/syncthing/syncthing/releases/tag/v1.15.0 Release Notes  Third Party Advisory 
https://github.com/syncthing/syncthing/security/advisories/GHSA-x462-89pf-6r5h Third Party Advisory 
https://pkg.go.dev/github.com/syncthing/syncthing Product  Third Party Advisory 

Weakness Enumeration

CWE-ID CWE Name Source
CWE-20 Improper Input Validation Provider acceptance level GitHub, Inc.  

Known Affected Software Configurations Switch to CPE 2.2

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Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2021-21404
NVD Published Date:
04/06/2021
NVD Last Modified:
04/14/2021
Source:
GitHub, Inc.