CVE-2021-32813Medium· 4.8▾ SunlitHeader dropping in traefik
▾ Sunlit zone — Low / medium · no exploitation signal
impact 26.4 · likelihood 0.2 · exploitation 0
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Exploit-prediction probability, daily snapshots since Jul 9.
Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via OSV
Last analysed / modified upstream
1.1%
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.
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.
Traefik v2.4.x: https://github.com/traefik/traefik/releases/tag/v2.4.13
No.
If you have any questions or comments about this advisory, open an issue.
github.com/traefik/traefik/v2 < 2.4.13github.com/traefik/traefik <= 1.7.30Upgrade to a patched release:
github.com/traefik/traefik/v2 2.4.13Connected by shared product, vendor, weakness, or advisory.
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