Vulnerability 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.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Linux | Linux Kernel | >= 2.6.26, < 6.6.79 |
Related Weaknesses (CWE)
References
- https://git.kernel.org/stable/c/087c1faa594fa07a66933d750c0b2610aa1a2946Patch
- https://git.kernel.org/stable/c/0bf8e2f3768629d437a32cb824149e6e98254381Patch
- https://git.kernel.org/stable/c/81b25a07ebf53f9ef4ca8f3d96a8ddb94561dd5aPatch
- https://git.kernel.org/stable/c/8e92d6a413feaf968a33f0b439ecf27404407458Patch
FAQ
What is CVE-2025-21759?
CVE-2025-21759 is a vulnerability with a CVSS score of 7.8 (HIGH). 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 protecti...
How severe is CVE-2025-21759?
CVE-2025-21759 has been rated HIGH with a CVSS base score of 7.8/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2025-21759?
Check the references section above for vendor advisories and patch information. Affected products include: Linux Linux Kernel.