{"id":"CVE-2025-21759","summary":"ipv6: mcast: extend RCU protection in igmp6_send()","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nipv6: mcast: extend RCU protection in igmp6_send()\n\nigmp6_send() can be called without RTNL or RCU being held.\n\nExtend RCU protection so that we can safely fetch the net pointer\nand avoid a potential UAF.\n\nNote that we no longer can use sock_alloc_send_skb() because\nipv6.igmp_sk uses GFP_KERNEL allocations which can sleep.\n\nInstead use alloc_skb() and charge the net-\u003eipv6.igmp_sk\nsocket under RCU protection.","modified":"2026-03-20T12:41:09.785939Z","published":"2025-02-27T02:18:12.994Z","related":["ALSA-2025:10371","ALSA-2025:10379","ALSA-2025:13589","ALSA-2025:13590","SUSE-SU-2025:01919-1","SUSE-SU-2025:01951-1","SUSE-SU-2025:01967-1","SUSE-SU-2025:1177-1","SUSE-SU-2025:1178-1","SUSE-SU-2025:1180-1","SUSE-SU-2025:1293-1","SUSE-SU-2025:20190-1","SUSE-SU-2025:20192-1","SUSE-SU-2025:20260-1","SUSE-SU-2025:20270-1","USN-7521-2"],"database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/21xxx/CVE-2025-21759.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/087c1faa594fa07a66933d750c0b2610aa1a2946"},{"type":"WEB","url":"https://git.kernel.org/stable/c/0bf8e2f3768629d437a32cb824149e6e98254381"},{"type":"WEB","url":"https://git.kernel.org/stable/c/81b25a07ebf53f9ef4ca8f3d96a8ddb94561dd5a"},{"type":"WEB","url":"https://git.kernel.org/stable/c/8e92d6a413feaf968a33f0b439ecf27404407458"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/21xxx/CVE-2025-21759.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-21759"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"b8ad0cbc58f703972e9e37c4e2a8081dd7e6a551"},{"fixed":"81b25a07ebf53f9ef4ca8f3d96a8ddb94561dd5a"},{"fixed":"0bf8e2f3768629d437a32cb824149e6e98254381"},{"fixed":"8e92d6a413feaf968a33f0b439ecf27404407458"},{"fixed":"087c1faa594fa07a66933d750c0b2610aa1a2946"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2025-21759.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"}]}