CVE-2025-21759
Published: February 28, 2025Last modified: October 6, 2026
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.
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score | 7.8 |
| Attack Vector | LOCAL |
| Attack complexity | LOW |
| Privileges required | LOW |
| User interaction | NONE |
| Scope | UNCHANGED |
| Confidentiality | HIGH |
| Integrity impact | HIGH |
| Availability impact | HIGH |
| Vector | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
Status
| Product | Release | Package | Status |
|---|---|---|---|
| Alpaquita Linux | 23 LTS | linux-lts | Fixed (6.1.189-r0) |
| 25 LTS | linux-lts | Fixed (6.12.41-r0) | |
| Stream | linux-lts | Fixed (6.18.35-r1) |
References
- https://git.kernel.org/stable/c/087c1faa594fa07a66933d750c0b2610aa1a2946
- https://git.kernel.org/stable/c/0bf8e2f3768629d437a32cb824149e6e98254381
- https://git.kernel.org/stable/c/638e8fe3563a82f298fe537a28d5342a97278cf1
- https://git.kernel.org/stable/c/6901bbb169e3add6c037218d996790cef6b3d650
- https://git.kernel.org/stable/c/7e0a818ecc4d62e7fb668ea02de0bfe8ba0b7dff
- https://git.kernel.org/stable/c/81b25a07ebf53f9ef4ca8f3d96a8ddb94561dd5a
- https://git.kernel.org/stable/c/8e92d6a413feaf968a33f0b439ecf27404407458