CVE-2024-36971

Basic Information

CVE State

PUBLISHED

Reserved Date

May 30, 2024

Published Date

June 10, 2024

Last Updated

December 19, 2024

Vendor

Linux

Product

Linux

Description

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.

CVSS Scores

SSVC Information

Exploitation

active

Technical Impact

total

Exploit Status

Exploited in the Wild

Yes (added 2024-08-07 00:00:00 UTC) Source