Description
In the Linux kernel, the following vulnerability has been resolved: net: do not send ICMP/NDISC Redirects when peer allocation fails When inet_getpeer_v4() or inet_getpeer_v6() fails to allocate a peer entry under memory pressure or tree size caps, redirect handlers previously fell back to sending un-rate-limited ICMP/NDISC Redirect messages. In IPv4, ip_rt_send_redirect() called icmp_send() directly when peer == NULL. In IPv6, ip6_forward() and ndisc_send_redirect() passed a NULL peer into inet_peer_xrlim_allow(), which returned true when peer == NULL. Because ICMP/NDISC Redirects are not part of the default global rate limit mask (sysctl_icmp_ratemask), sending redirects when peer == NULL creates an un-rate-limited ICMP packet storm. Fix this by failing closed in ip_rt_send_redirect(), ip6_forward(), and ndisc_send_redirect() when peer is NULL.
References6
- git.kernel.org/stable/c/21666f7af49a90ef44d474916b8ef4402dfd74f5
- git.kernel.org/stable/c/5ec5f00fc606a6df8434948c4552b3cb1176595d
- git.kernel.org/stable/c/828f6670d110ff2bf44c743037b38badc315704c
- git.kernel.org/stable/c/c0adf8b4247bcc5a145a25c1929006eb392580bb
- git.kernel.org/stable/c/dbc3791e3b2472e1ccc08947e0f83b443470ff4f
- git.kernel.org/stable/c/f5ecaa7ea7686fa7ecdb6affc9d3a9a42e4524b1
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 0% percentile: 42 · as of 11 November 2026
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