Impact
There is a potential vulnerability in Traefik managing the TLS connections.
A router configured with a not well-formatted TLSOption is exposed with an empty TLSOption.
For instance, a route secured using an mTLS connection set with a wrong CA file is exposed without verifying the client certificates.
Patches
https://github.com/traefik/traefik/releases/tag/v2.9.6
Workarounds
Check the logs to detect the following error messages and fix your TLS options:
{"level":"error","msg":"invalid clientAuthType: RequireAndVerifyClientCert, CAFiles is required","routerName":"Router0@file"}
- Bad CA content (or bad path):
{"level":"error","msg":"invalid certificate(s) content","routerName":"Router0@file"}
- Unknown Client Auth Type:
{"level":"error","msg":"unknown client auth type \"FooClientAuthType\"","routerName":"Router0@file"}
{"level":"error","msg":"invalid CipherSuite: foobar","routerName":"Router0@file"}
{"level":"error","msg":"invalid CurveID in curvePreferences: foobar","routerName":"Router0@file"}
For more information
If you have any questions or comments about this advisory, please open an issue.
References
Impact
There is a potential vulnerability in Traefik managing the TLS connections.
A router configured with a not well-formatted TLSOption is exposed with an empty TLSOption.
For instance, a route secured using an mTLS connection set with a wrong CA file is exposed without verifying the client certificates.
Patches
https://github.com/traefik/traefik/releases/tag/v2.9.6
Workarounds
Check the logs to detect the following error messages and fix your TLS options:
For more information
If you have any questions or comments about this advisory, please open an issue.
References