Threats Tagged 'cve-2026-53259'

The kernel packages contain the Linux kernel, the core of any Linux operating system. Security Fix(es): * kernel: can: bcm: add locking for bcm_op runtime updates (CVE-2025-38004) * kernel: ipv6: add NULL checks for idev in SRv6 paths (CVE-2026-23442) * kernel: udp: Fix wildcard bind conflict check when using hash2 (CVE-2026-31503) * kernel: ipv6: prevent possible UaF in addrconf_permanent_addr() (CVE-2026-43339) * kernel: tcp: call sk_data_ready() after listener migration (CVE-2026-46015) * kernel: inet: RAW sockets using IPPROTO_RAW MUST drop incoming ICMP (CVE-2026-46266) * kernel: flow_dissector: do not dissect PPPoE PFC frames (CVE-2026-46306) * kernel: io_uring/poll: fix signed comparison in io_poll_get_ownership() (CVE-2026-52933) * kernel: ppp: require CAP_NET_ADMIN in target netns for unattached ioctls (CVE-2026-53075) * kernel: KVM: arm64: Take the SRCU lock for page table walks in fault injection and AT emulation (CVE-2026-53277) * kernel: ipv6: sit: reload inner IPv6 header after GSO offloads (CVE-2026-53228) * kernel: net: add pskb_may_pull() to skb_gro_receive_list() (CVE-2026-53235) * kernel: net: guard timestamp cmsgs to real error queue skbs (CVE-2026-53223) * kernel: ipv6: mcast: Fix use-after-free when processing MLD queries (CVE-2026-53275) * kernel: ipv6: anycast: insert aca into global hash under idev->lock (CVE-2026-53259) * kernel: ipv4: free net->ipv4.sysctl_local_reserved_ports after unregister_net_sysctl_table() (CVE-2026-64002) * kernel: vxlan: do not reuse cached ip_hdr() value after skb_tunnel_check_pmtu() (CVE-2026-63993) * kernel: fuse: clear intr_entry in fuse_resend and fuse_remove_pending_req (CVE-2026-64265) * kernel: nvmet-auth: validate reply message payload bounds against transfer length (CVE-2026-64319) * kernel: KVM: arm64: Bound used_lrs when flushing the pKVM hyp vCPU (CVE-2026-64287) * kernel: rhashtable: clear stale iter->p on table restart (CVE-2026-64563) * kernel: smb: client: fix double-free in SMB2_close() replay (CVE-2026-64597) Bug Fix(es) and Enhancement(s): * Customer needs "netfilter: nfnetlink_queue: optimize verdict lookup with hash table" patch [RHEL 10.2] (JIRA:RHEL-132852) For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

In the Linux kernel, the following vulnerability has been resolved: ipv6: anycast: insert aca into global hash under idev->lock syzbot reported a splat [1]: a slab-use-after-free in ipv6_chk_acast_addr(), which walks the global inet6_acaddr_lst[] hash under RCU and dereferences a struct ifacaddr6 that has already been freed while still linked in the hash, so a later reader walks into a dangling node. In __ipv6_dev_ac_inc() the aca is allocated with refcount 1, then aca_get() bumps it to 2 to keep it alive across the unlocked region. It is published to idev->ac_list under idev->lock, but ipv6_add_acaddr_hash() runs after write_unlock_bh(). A concurrent teardown (ipv6_ac_destroy_dev() from addrconf_ifdown(), under RTNL) can slip into that window: CPU0 __ipv6_dev_ac_inc CPU1 ipv6_ac_destroy_dev (RTNL) ------------------------------ ------------------------------------ aca_alloc() refcnt 1 aca_get() refcnt 2 write_lock_bh(idev->lock) add aca to ac_list write_unlock_bh(idev->lock) write_lock_bh(idev->lock) pull aca off ac_list write_unlock_bh(idev->lock) ipv6_del_acaddr_hash(aca) hlist_del_init_rcu() is a no-op, aca is not in the hash yet aca_put() refcnt 2->1 ipv6_add_acaddr_hash(aca) aca now inserted into the hash aca_put() refcnt 1->0 call_rcu(aca_free_rcu) -> kfree(aca) The hash removal becomes a no-op because the insertion has not happened yet, so once CPU0 inserts and drops the last reference, the aca is freed while still linked in inet6_acaddr_lst[], and readers dereference freed memory after the slab slot is reused. This window opened once RTNL stopped serializing the join path against device teardown. Move ipv6_add_acaddr_hash() inside the idev->lock section so the ac_list and hash insertions are atomic with respect to teardown: a racing remover now either misses the aca entirely or finds it in both lists. acaddr_hash_lock is now nested under idev->lock, which is acquired in softirq context, so switch all acaddr_hash_lock sites to spin_lock_bh() to avoid the irq lock inversion reported in [2]. [1] https://syzkaller.appspot.com/bug?extid=a01df04303c131efbf3a [2] https://lore.kernel.org/netdev/[email protected]/