GHSA-C8V5-2JCX-X4J2
Vulnerability from github – Published: 2024-02-28 09:30 – Updated: 2024-08-07 18:30In the Linux kernel, the following vulnerability has been resolved:
net: Only allow init netns to set default tcp cong to a restricted algo
tcp_set_default_congestion_control() is netns-safe in that it writes to &net->ipv4.tcp_congestion_control, but it also sets ca->flags |= TCP_CONG_NON_RESTRICTED which is not namespaced. This has the unintended side-effect of changing the global net.ipv4.tcp_allowed_congestion_control sysctl, despite the fact that it is read-only: 97684f0970f6 ("net: Make tcp_allowed_congestion_control readonly in non-init netns")
Resolve this netns "leak" by only allowing the init netns to set the default algorithm to one that is restricted. This restriction could be removed if tcp_allowed_congestion_control were namespace-ified in the future.
This bug was uncovered with https://github.com/JonathonReinhart/linux-netns-sysctl-verify
{
"affected": [],
"aliases": [
"CVE-2021-47010"
],
"database_specific": {
"cwe_ids": [
"CWE-400"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-02-28T09:15:38Z",
"severity": "HIGH"
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: Only allow init netns to set default tcp cong to a restricted algo\n\ntcp_set_default_congestion_control() is netns-safe in that it writes\nto \u0026net-\u003eipv4.tcp_congestion_control, but it also sets\nca-\u003eflags |= TCP_CONG_NON_RESTRICTED which is not namespaced.\nThis has the unintended side-effect of changing the global\nnet.ipv4.tcp_allowed_congestion_control sysctl, despite the fact that it\nis read-only: 97684f0970f6 (\"net: Make tcp_allowed_congestion_control\nreadonly in non-init netns\")\n\nResolve this netns \"leak\" by only allowing the init netns to set the\ndefault algorithm to one that is restricted. This restriction could be\nremoved if tcp_allowed_congestion_control were namespace-ified in the\nfuture.\n\nThis bug was uncovered with\nhttps://github.com/JonathonReinhart/linux-netns-sysctl-verify",
"id": "GHSA-c8v5-2jcx-x4j2",
"modified": "2024-08-07T18:30:38Z",
"published": "2024-02-28T09:30:37Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2021-47010"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/6c1ea8bee75df8fe2184a50fcd0f70bf82986f42"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/8d432592f30fcc34ef5a10aac4887b4897884493"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/9884f745108f7d25b189bbcd6754e284fb29ab68"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/992de06308d9a9584d59b96d294ac676f924e437"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/e7d7bedd507bb732e600403b7a96f9fe48d0ca31"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/efe1532a6e1a8e3c343d04fff510f0ed80328f9c"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
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