{"id":"AZL-56268","summary":"CVE-2025-21683 affecting package kernel for versions less than 5.15.180.1-1","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Fix bpf_sk_select_reuseport() memory leak\n\nAs pointed out in the original comment, lookup in sockmap can return a TCP\nESTABLISHED socket. Such TCP socket may have had SO_ATTACH_REUSEPORT_EBPF\nset before it was ESTABLISHED. In other words, a non-NULL sk_reuseport_cb\ndoes not imply a non-refcounted socket.\n\nDrop sk's reference in both error paths.\n\nunreferenced object 0xffff888101911800 (size 2048):\n  comm \"test_progs\", pid 44109, jiffies 4297131437\n  hex dump (first 32 bytes):\n    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................\n    80 00 01 00 00 00 00 00 00 00 00 00 00 00 00 00  ................\n  backtrace (crc 9336483b):\n    __kmalloc_noprof+0x3bf/0x560\n    __reuseport_alloc+0x1d/0x40\n    reuseport_alloc+0xca/0x150\n    reuseport_attach_prog+0x87/0x140\n    sk_reuseport_attach_bpf+0xc8/0x100\n    sk_setsockopt+0x1181/0x1990\n    do_sock_setsockopt+0x12b/0x160\n    __sys_setsockopt+0x7b/0xc0\n    __x64_sys_setsockopt+0x1b/0x30\n    do_syscall_64+0x93/0x180\n    entry_SYSCALL_64_after_hwframe+0x76/0x7e","modified":"2026-04-01T05:18:51.099167Z","published":"2025-01-31T12:15:29Z","upstream":["CVE-2025-21683"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-21683"}],"affected":[{"package":{"name":"kernel","ecosystem":"Azure Linux:2","purl":"pkg:rpm/azure-linux/kernel"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"5.15.180.1-1"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-56268.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:N/I:N/A:H"}]}