{"id":"CVE-2026-74550","aliases":[],"url":"https://o3.security/vulnerability/CVE-2026-74550","summary":"net: do not send ICMP/NDISC Redirects when peer allocation fails","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: do not send ICMP/NDISC Redirects when peer allocation fails\n\nWhen inet_getpeer_v4() or inet_getpeer_v6() fails to allocate a peer entry\nunder memory pressure or tree size caps, redirect handlers previously fell\nback to sending un-rate-limited ICMP/NDISC Redirect messages.\n\nIn IPv4, ip_rt_send_redirect() called icmp_send() directly when peer == NULL.\nIn IPv6, ip6_forward() and ndisc_send_redirect() passed a NULL peer into\ninet_peer_xrlim_allow(), which returned true when peer == NULL.\n\nBecause ICMP/NDISC Redirects are not part of the default global rate limit\nmask (sysctl_icmp_ratemask), sending redirects when peer == NULL creates\nan un-rate-limited ICMP packet storm.\n\nFix this by failing closed in ip_rt_send_redirect(), ip6_forward(), and\nndisc_send_redirect() when peer is NULL.","published":"2026-08-15T12:27:57.615Z","modified":"2026-08-18T03:56:30.533336295Z","cvss":{"score":7.5,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},"epss":null,"cisaKev":null,"exploitsKnown":null,"affectedPackages":[{"ecosystem":"Linux","name":"Kernel","fixedVersion":"6.6.151"}],"fix":null,"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/21666f7af49a90ef44d474916b8ef4402dfd74f5"},{"type":"WEB","url":"https://git.kernel.org/stable/c/5ec5f00fc606a6df8434948c4552b3cb1176595d"},{"type":"WEB","url":"https://git.kernel.org/stable/c/828f6670d110ff2bf44c743037b38badc315704c"},{"type":"WEB","url":"https://git.kernel.org/stable/c/dbc3791e3b2472e1ccc08947e0f83b443470ff4f"},{"type":"WEB","url":"https://git.kernel.org/stable/c/f5ecaa7ea7686fa7ecdb6affc9d3a9a42e4524b1"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/74xxx/CVE-2026-74550.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-74550"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-18T03:56:30.533336295Z"}}