{"apiVersion":"1.0","identifier":"CVE-2026-74562","description":"In the Linux kernel, the following vulnerability has been resolved: nexthop: take nh->lock for f6i_list walks in replace check and notify fib6_check_nh_list() and __nexthop_replace_notify() walk nh->f6i_list during an RTNL-serialized nexthop replace without holding nh->lock. IPv6 RTM_NEWROUTE/RTM_DELROUTE run without RTNL and mutate that list under nh->lock (fib6_add_rt2node_nh(), fib6_purge_rt()), so both walks race a concurrent route delete that unlinks and frees a fib6_info: BUG: KASAN: slab-use-after-free in rt6_fill_node.isra.0 (net/ipv6/route.c:5799) Read of size 4 at addr ffff888014607e64 by task exploit/143 rt6_fill_node.isra.0 (net/ipv6/route.c:5799) fib6_rt_update (net/ipv6/route.c:6412) __nexthop_replace_notify (net/ipv4/nexthop.c:2542) rtm_new_nexthop (net/ipv4/nexthop.c:2554) rtnetlink_rcv_msg (net/core/rtnetlink.c:7076) BUG: KASAN: slab-use-after-free in fib6_check_nh_list (net/ipv4/nexthop.c:1605) Read of size 8 at addr ffff888014a7d068 by task exploit/142 fib6_check_nh_list (net/ipv4/nexthop.c:1605) rtm_new_nexthop (net/ipv4/nexthop.c:2575) rtnetlink_rcv_msg (net/core/rtnetlink.c:7076) Both walks only read the entries and take no tb6_lock, so protect them with nh->lock; fib6_rt_update() uses gfp_any(), which returns GFP_ATOMIC under the lock.","publishedAt":"2026-08-15T13:18:01","lastModifiedAt":"2026-08-17T06:19:54","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-74562","cvssScore":8.8,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H","epssProbability":0.00113,"riskScore":0.89,"affectedProduct":"Linux kernel","affectedVersions":"unknown","vulnerabilityType":"Kernel","operatingSystems":[],"links":{"self":"https://www.redsauce.net/api/cves/CVE-2026-74562","webPages":{"es":"https://www.redsauce.net/es/cves/CVE-2026-74562","en":"https://www.redsauce.net/en/cves/CVE-2026-74562","fr":"https://www.redsauce.net/fr/cves/CVE-2026-74562","pt":"https://www.redsauce.net/pt/cves/CVE-2026-74562","de":"https://www.redsauce.net/de/cves/CVE-2026-74562","sk":"https://www.redsauce.net/sk/cves/CVE-2026-74562","el":"https://www.redsauce.net/el/cves/CVE-2026-74562"},"source":"https://nvd.nist.gov/vuln/detail/CVE-2026-74562"}}