GHSA-m697-4v8f-55qg
Header dropping in traefik
Packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| Go | github.com/traefik/traefik/v2 | < 2.4.13 | 2.4.13 |
| Go | github.com/traefik/traefik | <= 1.7.30 | no fix listed |
Details
As written in the advisory (Markdown source, shown as plain text).
# Impact
There exists a potential header vulnerability in Traefik's handling of the Connection header. Active exploitation of this issue is unlikely, as it requires that a removed header would lead to a privilege escalation, however, the Traefik team has addressed this issue to prevent any potential abuse.
# Details
If you have a chain of Traefik middlewares, and one of them sets a request header `Important-Security-Header`, then sending a request with the following Connection header will cause it to be removed before the request was sent:
```
curl 'https://example.com' -H "Connection: Important-Security-Header" -0
```
In this case, the backend does not see the request header `Important-Security-Header`.
# Patches
Traefik v2.4.x: https://github.com/traefik/traefik/releases/tag/v2.4.13
# Workarounds
No.
# For more information
If you have any questions or comments about this advisory, [open an issue](https://github.com/traefik/traefik/issues).
References
External links from the advisory. They lead to third-party sites.