GHSA-h2ph-vhm7-g4hp Traefik may display authorization header in the debug logs

• Go github.com/traefik/traefik/v2: < 2.9.6 → fixed in 2.9.6

Impact There is a potential vulnerability in Traefik displaying the Authorization header in its debug logs. Traefik uses oxy to provide the following features: • Round Robin: https://doc.traefik.io/traefik/routing/services/#weighted-round-robin-service • Buffering: https://doc.traefik.io/traefik/middlewares/http/buffering/ • Circuit Breaker: https://doc.traefik.io/traefik/middlewares/http/circuitbreaker/ • In-Flight Requests: https://doc.traefik.io/traefik/middlewares/http/inflightreq/ In such cases, if the log level is set to DEBUG, the credentials provided using the Authorization header are displayed in the debug logs: ``` level=debug msg="vulcand/oxy/roundrobin/rr: completed ServeHttp on request" Request="{\\"Method\\":\\"POST\\",\\"URL\\":{\\"Scheme\\":\\"\\",\\"Opaque\\":\\"\\",\\"User\\":null,\\"Host\\":\\"\\",\\"Path\\":\\"//\\",\\"RawPath\\":\\"\\",\\"ForceQuery\\":false,\\"RawQuery\\":\\"\\",\\"Fragment\\":\\"\\",\\"RawFragment\\":\\"\\"},\\"Proto\\":\\"HTTP/2.0\\",\\"ProtoMajor\\":2,\\"ProtoMinor\\":0,\\"Header\\":{\\"Authorization\\":[\\"Bearer \\"],\\"Content-Type\\":[\\"application/grpc\\"],\\"Grpc-Accept-Encoding\\":[\\"gzip\\"],\\"Grpc-Timeout\\":[\\"29999886u\\"],\\"Te\\":[\\"trailers\\"],\\"User-Agent\\":[\\"\\"], ``` Patches https://github.com/traefik/traefik/pull/9574 https://github.com/traefik/traefik/releases/tag/v2.9.6 Workarounds Set the log level to `INFO`, `WARN`, or `ERROR`. For more information If you have any questions or comments about this advisory, please open an issue.