CVE-2025-21759

high

Description

In the Linux kernel, the following vulnerability has been resolved: ipv6: mcast: extend RCU protection in igmp6_send() igmp6_send() can be called without RTNL or RCU being held. Extend RCU protection so that we can safely fetch the net pointer and avoid a potential UAF. Note that we no longer can use sock_alloc_send_skb() because ipv6.igmp_sk uses GFP_KERNEL allocations which can sleep. Instead use alloc_skb() and charge the net->ipv6.igmp_sk socket under RCU protection.

References

https://git.kernel.org/stable/c/8e92d6a413feaf968a33f0b439ecf27404407458

https://git.kernel.org/stable/c/81b25a07ebf53f9ef4ca8f3d96a8ddb94561dd5a

https://git.kernel.org/stable/c/7e0a818ecc4d62e7fb668ea02de0bfe8ba0b7dff

https://git.kernel.org/stable/c/6901bbb169e3add6c037218d996790cef6b3d650

https://git.kernel.org/stable/c/638e8fe3563a82f298fe537a28d5342a97278cf1

https://git.kernel.org/stable/c/0bf8e2f3768629d437a32cb824149e6e98254381

https://git.kernel.org/stable/c/087c1faa594fa07a66933d750c0b2610aa1a2946

https://euvd.enisa.europa.eu/vulnerability/EUVD-2025-5157

Details

Source: Mitre, NVD

Published: 2025-02-27

Updated: 2026-10-03

Risk Information

CVSS v2

Base Score: 6.8

Vector: CVSS2#AV:L/AC:L/Au:S/C:C/I:C/A:C

Severity: Medium

CVSS v3

Base Score: 7.8

Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Severity: High

EPSS

EPSS: 0.07804