{"cve":"CVE-2025-21683","nvd":{"published":"2025-01-31T12:15:29.460","modified":"2026-06-17T08:44:00.843","status":"Modified","description":"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","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":5.5},"cwes":["CWE-401"],"references":["https://git.kernel.org/stable/c/0ab52a8ca6e156a64c51b5e7456cac9a0ebfd9bf","https://git.kernel.org/stable/c/b02e70be498b138e9c21701c2f33f4018ca7cd5e","https://git.kernel.org/stable/c/b3af60928ab9129befa65e6df0310d27300942bf","https://git.kernel.org/stable/c/bb36838dac7bb334a3f3d7eb29875593ec9473fc","https://git.kernel.org/stable/c/cccd51dd22574216e64e5d205489e634f86999f3"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T21:58:41.599736885+00:00"},"epss":{"cve":"CVE-2025-21683","score":0.00224,"percentile":0.13051,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}