ghsa-3rf3-8wmx-cm8q
Vulnerability from github
In the Linux kernel, the following vulnerability has been resolved:
net: fix __dst_negative_advice() race
__dst_negative_advice() does not enforce proper RCU rules when sk->dst_cache must be cleared, leading to possible UAF.
RCU rules are that we must first clear sk->sk_dst_cache, then call dst_release(old_dst).
Note that sk_dst_reset(sk) is implementing this protocol correctly, while __dst_negative_advice() uses the wrong order.
Given that ip6_negative_advice() has special logic against RTF_CACHE, this means each of the three ->negative_advice() existing methods must perform the sk_dst_reset() themselves.
Note the check against NULL dst is centralized in __dst_negative_advice(), there is no need to duplicate it in various callbacks.
Many thanks to Clement Lecigne for tracking this issue.
This old bug became visible after the blamed commit, using UDP sockets.
{
"affected": [],
"aliases": [
"CVE-2024-36971"
],
"database_specific": {
"cwe_ids": [
"CWE-416"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-06-10T09:15:09Z",
"severity": "HIGH"
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: fix __dst_negative_advice() race\n\n__dst_negative_advice() does not enforce proper RCU rules when\nsk-\u003edst_cache must be cleared, leading to possible UAF.\n\nRCU rules are that we must first clear sk-\u003esk_dst_cache,\nthen call dst_release(old_dst).\n\nNote that sk_dst_reset(sk) is implementing this protocol correctly,\nwhile __dst_negative_advice() uses the wrong order.\n\nGiven that ip6_negative_advice() has special logic\nagainst RTF_CACHE, this means each of the three -\u003enegative_advice()\nexisting methods must perform the sk_dst_reset() themselves.\n\nNote the check against NULL dst is centralized in\n__dst_negative_advice(), there is no need to duplicate\nit in various callbacks.\n\nMany thanks to Clement Lecigne for tracking this issue.\n\nThis old bug became visible after the blamed commit, using UDP sockets.",
"id": "GHSA-3rf3-8wmx-cm8q",
"modified": "2024-06-27T12:30:47Z",
"published": "2024-06-10T09:31:06Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2024-36971"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/051c0bde9f0450a2ec3d62a86d2a0d2fad117f13"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/2295a7ef5c8c49241bff769e7826ef2582e532a6"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/5af198c387128a9d2ddd620b0f0803564a4d4508"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/81dd3c82a456b0015461754be7cb2693991421b4"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/92f1655aa2b2294d0b49925f3b875a634bd3b59e"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/b8af8e6118a6605f0e495a58d591ca94a85a50fc"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/db0082825037794c5dba9959c9de13ca34cc5e72"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/eacb8b195579c174a6d3e12a9690b206eb7f28cf"
},
{
"type": "WEB",
"url": "https://lists.debian.org/debian-lts-announce/2024/06/msg00020.html"
}
],
"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"
}
]
}
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.