In the Linux kernel, the following vulnerability has been resolved: net: do not send ICMP/NDISC...
🔗 CVE IDs covered (1)
📋 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.
🔗 References (8)
- https://nvd.nist.gov/vuln/detail/CVE-2026-74550
- https://git.kernel.org/stable/c/21666f7af49a90ef44d474916b8ef4402dfd74f5
- https://git.kernel.org/stable/c/5ec5f00fc606a6df8434948c4552b3cb1176595d
- https://git.kernel.org/stable/c/828f6670d110ff2bf44c743037b38badc315704c
- https://git.kernel.org/stable/c/dbc3791e3b2472e1ccc08947e0f83b443470ff4f
- https://git.kernel.org/stable/c/f5ecaa7ea7686fa7ecdb6affc9d3a9a42e4524b1
- https://git.kernel.org/stable/c/c0adf8b4247bcc5a145a25c1929006eb392580bb
- https://github.com/advisories/GHSA-9cch-cjjm-3m2c