{"id":"CVE-2026-74550","title":"net: do not send ICMP/NDISC Redirects when peer allocation fails","summary":"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 tr…","severity":"high","cvss":7.5,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","cvssSource":"cna","vendor":"Linux","product":"Linux","affected":["Linux >= 92d8682926342d2b6aa5b2ecc02221e00e1573a0 < c0adf8b4247bcc5a145a25c1929006eb392580bb","Linux >= 92d8682926342d2b6aa5b2ecc02221e00e1573a0 < f5ecaa7ea7686fa7ecdb6affc9d3a9a42e4524b1","Linux >= 92d8682926342d2b6aa5b2ecc02221e00e1573a0 < 21666f7af49a90ef44d474916b8ef4402dfd74f5","Linux >= 92d8682926342d2b6aa5b2ecc02221e00e1573a0 < 5ec5f00fc606a6df8434948c4552b3cb1176595d","Linux >= 92d8682926342d2b6aa5b2ecc02221e00e1573a0 < 828f6670d110ff2bf44c743037b38badc315704c","Linux >= 92d8682926342d2b6aa5b2ecc02221e00e1573a0 < dbc3791e3b2472e1ccc08947e0f83b443470ff4f","Linux 2.6.39"],"ssvc":{"exploitation":"none","automatable":"yes","technicalImpact":"partial","timestamp":"2026-10-16T18:59:55.162783Z"},"published":"2026-08-15","updated":"2026-10-16","sourceUpdated":"2026-10-16T19:05:55.243Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-74550","references":[{"url":"https://git.kernel.org/stable/c/c0adf8b4247bcc5a145a25c1929006eb392580bb"},{"url":"https://git.kernel.org/stable/c/f5ecaa7ea7686fa7ecdb6affc9d3a9a42e4524b1"},{"url":"https://git.kernel.org/stable/c/21666f7af49a90ef44d474916b8ef4402dfd74f5"},{"url":"https://git.kernel.org/stable/c/5ec5f00fc606a6df8434948c4552b3cb1176595d"},{"url":"https://git.kernel.org/stable/c/828f6670d110ff2bf44c743037b38badc315704c"},{"url":"https://git.kernel.org/stable/c/dbc3791e3b2472e1ccc08947e0f83b443470ff4f"}],"tags":["cve.org"],"epss":0.00479,"epssPercentile":0.3993,"ingestedAt":"2026-10-16T19:46:24.345Z","slug":"CVE-2026-74550","body":"## Overview\n\nIn 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.\n\n## Affected\n\n- `Linux >= 92d8682926342d2b6aa5b2ecc02221e00e1573a0 < c0adf8b4247bcc5a145a25c1929006eb392580bb`\n- `Linux >= 92d8682926342d2b6aa5b2ecc02221e00e1573a0 < f5ecaa7ea7686fa7ecdb6affc9d3a9a42e4524b1`\n- `Linux >= 92d8682926342d2b6aa5b2ecc02221e00e1573a0 < 21666f7af49a90ef44d474916b8ef4402dfd74f5`\n- `Linux >= 92d8682926342d2b6aa5b2ecc02221e00e1573a0 < 5ec5f00fc606a6df8434948c4552b3cb1176595d`\n- `Linux >= 92d8682926342d2b6aa5b2ecc02221e00e1573a0 < 828f6670d110ff2bf44c743037b38badc315704c`\n- `Linux >= 92d8682926342d2b6aa5b2ecc02221e00e1573a0 < dbc3791e3b2472e1ccc08947e0f83b443470ff4f`\n- `Linux 2.6.39`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":41,"depthScoreParts":{"impact":41.3,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}