Affected: AlmaLinux:8: bpftool, AlmaLinux:8: kernel, AlmaLinux:8: kernel-abi-stablelists, AlmaLinux:8: kernel-core, AlmaLinux:8: kernel-cross-headers, AlmaLinux:8: kernel-debug, AlmaLinux:8: kernel-debug-core, AlmaLinux:8: kernel-debug-devel, AlmaLinux:8: kernel-debug-modules, AlmaLinux:8: kernel-debug-modules-extra and 15 more

The kernel packages contain the Linux kernel, the core of any Linux operating system.

Security Fix(es):

* kernel: ipv6: exthdrs: refresh nh pointer after ipv6_hop_jumbo() (CVE-2026-63924) * kernel: ipv6: exthdrs: refresh nh after handling HAO option (CVE-2026-63922) * kernel: af_unix: Fix UAF read of tail->len in unix_stream_data_wait() (CVE-2026-64109) * kernel: scsi: target: core: Fix iSCSI ISID use-after-free in REGISTER AND MOVE (CVE-2026-72083) * kernel: tipc: require net admin for TIPCv2 netlink mutators (CVE-2026-74283) * kernel: smb: client: bound dirent name against end of SMB response in cifs_filldir (CVE-2026-93787) * kernel: ZDI-CAN-33367: Linux Kernel skbuff skb_zerocopy Improper Ownership Management Local Privilege Escalation Vulnerability ()

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:

net: skbuff: propagate shared-frag marker in skb_zerocopy()

skb_zerocopy() moves frag descriptors from @from into @to and takes a reference on each frag, but it does not copy skb_shinfo(from)->flags into skb_shinfo(to)->flags. A destination skb holding the same page-cache backed frags as the source therefore reports skb_has_shared_frag() as false.

That breaks the invariant relied on by later in-place writers. ESP input checks skb_has_shared_frag() before deciding whether an uncloned nonlinear skb can skip skb_cow_data(); with the marker lost, an skb that skb_zerocopy() built for nfnetlink_queue or for an openvswitch upcall is decrypted in place, letting an unprivileged user write into the page cache of a root-owned read-only file.

Propagate SKBFL_SHARED_FRAG when frag descriptors are copied, as done for the other frag-transfer helpers.

In the Linux kernel, the following vulnerability has been resolved:

net: skbuff: propagate shared-frag marker in skb_zerocopy()

skb_zerocopy() moves frag descriptors from @from into @to and takes a reference on each frag, but it does not copy skb_shinfo(from)->flags into skb_shinfo(to)->flags. A destination skb holding the same page-cache backed frags as the source therefore reports skb_has_shared_frag() as false.

That breaks the invariant relied on by later in-place writers. ESP input checks skb_has_shared_frag() before deciding whether an uncloned nonlinear skb can skip skb_cow_data(); with the marker lost, an skb that skb_zerocopy() built for nfnetlink_queue or for an openvswitch upcall is decrypted in place, letting an unprivileged user write into the page cache of a root-owned read-only file.

Propagate SKBFL_SHARED_FRAG when frag descriptors are copied, as done for the other frag-transfer helpers.

kernel: sctp: stream: fully roll back denied add-stream state kernel: ipv6: sit: reload inner IPv6 header after GSO offloads kernel: ipvs: clear the svc scheduler ptr early on edit kernel: spi: fsl-lpspi: terminate the RX channel on TX prepare failure path kernel: mptcp: pm: userspace: fix use-after-free in get_local_id kernel: scsi: target: core: Fix iSCSI ISID use-after-free in REGISTER AND MOVE kernel: tipc: require net admin for TIPCv2 netlink mutators kernel: Bluetooth: mgmt: fix UAF in pair command cancellation kernel: packet: use consistent hard_header_len in non-ring send paths kernel: mptcp: options: reset DSS fields in case of unexpected size kernel: scsi: target: iscsi: Reserve a terminator byte for the login payload kernel: smb: client: bound dirent name against end of SMB response in cifs_filldir kernel: virtio-fs: avoid double-free on failed queue setup kernel: xfrm: hold net_device reference under RCU in bundle creation kernel: ipv4: free inet_opt and ireq_opt after an RCU grace period kernel: KVM: arm64: Transfer the hyp stack pages out of the host stage-2 kernel: nvmet-auth: fix out-of-bounds write in nvmet_auth_challenge() kernel: kernel: privilege escalation via missing shared fragment flag in skb_zerocopy

Ein Angreifer kann mehrere Schwachstellen im Linux Kernel ausnutzen, um einen nicht näher spezifizierten Angriff durchzuführen, möglicherweise einen Denial-of-Service-Angriff auszulösen, Daten zu manipulieren oder offenzulegen oder Sicherheitsmaßnahmen zu umgehen.