{"schema_version":"1.7.5","id":"CVE-2026-23095","published":"2026-02-04T16:08:17.990Z","modified":"2026-07-16T03:31:16.761247987Z","related":["SUSE-SU-2026:0962-1","SUSE-SU-2026:1078-1","SUSE-SU-2026:1081-1","SUSE-SU-2026:20667-1","SUSE-SU-2026:20720-1","SUSE-SU-2026:20838-1","SUSE-SU-2026:20845-1","SUSE-SU-2026:20873-1","SUSE-SU-2026:20876-1","SUSE-SU-2026:20931-1","SUSE-SU-2026:21284-1","openSUSE-SU-2026:20416-1"],"summary":"gue: Fix skb memleak with inner IP protocol 0.","details":"In the Linux kernel, the following vulnerability has been resolved:\n\ngue: Fix skb memleak with inner IP protocol 0.\n\nsyzbot reported skb memleak below. [0]\n\nThe repro generated a GUE packet with its inner protocol 0.\n\ngue_udp_recv() returns -guehdr->proto_ctype for \"resubmit\"\nin ip_protocol_deliver_rcu(), but this only works with\nnon-zero protocol number.\n\nLet's drop such packets.\n\nNote that 0 is a valid number (IPv6 Hop-by-Hop Option).\n\nI think it is not practical to encap HOPOPT in GUE, so once\nsomeone starts to complain, we could pass down a resubmit\nflag pointer to distinguish two zeros from the upper layer:\n\n  * no error\n  * resubmit HOPOPT\n\n[0]\nBUG: memory leak\nunreferenced object 0xffff888109695a00 (size 240):\n  comm \"syz.0.17\", pid 6088, jiffies 4294943096\n  hex dump (first 32 bytes):\n    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................\n    00 40 c2 10 81 88 ff ff 00 00 00 00 00 00 00 00  .@..............\n  backtrace (crc a84b336f):\n    kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]\n    slab_post_alloc_hook mm/slub.c:4958 [inline]\n    slab_alloc_node mm/slub.c:5263 [inline]\n    kmem_cache_alloc_noprof+0x3b4/0x590 mm/slub.c:5270\n    __build_skb+0x23/0x60 net/core/skbuff.c:474\n    build_skb+0x20/0x190 net/core/skbuff.c:490\n    __tun_build_skb drivers/net/tun.c:1541 [inline]\n    tun_build_skb+0x4a1/0xa40 drivers/net/tun.c:1636\n    tun_get_user+0xc12/0x2030 drivers/net/tun.c:1770\n    tun_chr_write_iter+0x71/0x120 drivers/net/tun.c:1999\n    new_sync_write fs/read_write.c:593 [inline]\n    vfs_write+0x45d/0x710 fs/read_write.c:686\n    ksys_write+0xa7/0x170 fs/read_write.c:738\n    do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]\n    do_syscall_64+0xa4/0xf80 arch/x86/entry/syscall_64.c:94\n    entry_SYSCALL_64_after_hwframe+0x77/0x7f","affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"37dd0247797b168ad1cc7f5dbec825a1ee66535b"},{"fixed":"886f186328b718400dbf79e1bc8cbcbd710ab766"},{"fixed":"380a82d36e37db49fd41ecc378c22fd29392e96a"},{"fixed":"536f5bbc322eb1e175bdd1ced22b236a951c4d8f"},{"fixed":"f87b9b7a618c82e7465e872eb10e14c803871892"},{"fixed":"ce569b389a5c78d64788a5ea94560e17fa574b35"},{"fixed":"5437a279804ced8088cabb945dba88a26d828f8c"},{"fixed":"9a56796ad258786d3624eef5aefba394fc9bdded"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-23095.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"3.18.0"},{"fixed":"5.10.249"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.11.0"},{"fixed":"5.15.199"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.162"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.122"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.68"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.8"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-23095.json"}}],"references":[{"type":"WEB","url":"https://cert-portal.siemens.com/productcert/html/ssa-019113.html"},{"type":"WEB","url":"https://git.kernel.org/stable/c/380a82d36e37db49fd41ecc378c22fd29392e96a"},{"type":"WEB","url":"https://git.kernel.org/stable/c/536f5bbc322eb1e175bdd1ced22b236a951c4d8f"},{"type":"WEB","url":"https://git.kernel.org/stable/c/5437a279804ced8088cabb945dba88a26d828f8c"},{"type":"WEB","url":"https://git.kernel.org/stable/c/886f186328b718400dbf79e1bc8cbcbd710ab766"},{"type":"WEB","url":"https://git.kernel.org/stable/c/9a56796ad258786d3624eef5aefba394fc9bdded"},{"type":"WEB","url":"https://git.kernel.org/stable/c/ce569b389a5c78d64788a5ea94560e17fa574b35"},{"type":"WEB","url":"https://git.kernel.org/stable/c/f87b9b7a618c82e7465e872eb10e14c803871892"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/23xxx/CVE-2026-23095.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-23095"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/23xxx/CVE-2026-23095.json"},"severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"}]}