CVE-2026-74586
CriticalCVSS 9.8Exploitation Probability (EPSS)
Low risk41th percentile - higher than 41% of all known CVEs
Summary
A use-after-free vulnerability was found in the Linux kernel's SCTP subsystem. An authenticated remote SCTP peer can add and remove a transport within a single ASCONF chunk, leaving the new_transport pointer dangling. Subsequent operations (e.g., sending a HEARTBEAT) may read freed memory, as shown by a KASAN report in sctp_outq_select_transport.
Risk Assessment
The vulnerability could be exploited by an authenticated remote attacker to cause a kernel crash or potentially escalate privileges. However, it requires an authenticated SCTP connection, limiting risk in environments where SCTP is not used or properly secured.
Recommendation
Apply the official Linux kernel patch that clears new_transport when the peer is removed. Also consider restricting SCTP access via firewall and monitoring systems for unusual SCTP activity.
Other vulnerabilities in Linux kernel
See all- CVE-2026-98384Unknown
In the Linux kernel, bpf_sock_destroy() reads sk_protocol from the wrong structure, causing an out-of-bounds read. The issue affects TIME_WAIT and request sockets passed by the TCP iterator. The fix restricts the sk_protocol check to full sockets only.
- CVE-2026-98383Unknown
In the Linux kernel, LWT_SEG6LOCAL programs can invalidate the cached SRH and then call bpf_skb_pull_data(), leading to a dangling pointer and use-after-free. The fix disallows bpf_skb_pull_data() for LWT_SEG6LOCAL programs.
- CVE-2026-98382Unknown
In the Linux kernel, the BPF device matching mechanism has a flaw that allows a program bound to one device to run on another, leading to memory corruption. The fix restricts non-offloaded programs to exact netdev matches.
- CVE-2026-98381Unknown
In the Linux kernel, during veth channel resize, XDP program pointers are not cleared for removed RX queues. This can lead to running a freed program after a later channel increase, causing a system crash.
- CVE-2026-98380Unknown
In the Linux kernel's net/sched subsystem, a vulnerability exists where tcf_action_delete() fails to check if the IDR lookup result is an error pointer (ERR_PTR). An attacker can exploit a race to replace an action with an error pointer, leading to a null-pointer dereference and kernel panic.
- CVE-2026-98379Unknown
A vulnerability in the Linux kernel's netfilter ip6t_rpfilter module was found, where ip6_route_lookup() can return a route without an inet6_dev (NULL pointer). An unprivileged user can trigger this state by lowering an external interface's MTU below IPV6_MIN_MTU, leading to a NULL pointer dereference and kernel panic.
- CVE-2026-98378Unknown
In the Linux kernel, a vulnerability exists in the BPF link iterator. bpf_link_prime() inserts a link into link_idr before the ID is published, and the link iterator takes a reference without checking whether the link is settled (ID zero). If anon_inode_getfile() fails, the iterator is left with a dangling reference and a subsequent bpf_link_put() accesses freed memory (use-after-free).
- CVE-2026-98377Unknown
In the Linux kernel, __vlan_insert_inner_tag() does not require the MAC header to be present before rewriting it. When a very short frame is sent through an IFF_TUN device, subsequent VLAN push operations can pull uninitialized slab bytes into the frame, leaking kernel memory.
- CVE-2026-98376Unknown
In the Linux kernel, the metadata comparison for percpu array BPF maps used as inner maps does not check max_entries. Replacing an inner map with a smaller one bypasses validation, and the index_mask inlined by the JIT can cause an out-of-bounds access to the pptrs[] array.
- CVE-2026-98375Unknown
In the Linux kernel, the xen/netfront driver does not validate the length of the first RX slot against ETH_HLEN before calling eth_type_trans(). If the first slot is shorter than an Ethernet header, a BUG() may occur in __skb_pull() or the header may be read past the end of the data.
Original NVD description (English source)
In the Linux kernel, the following vulnerability has been resolved: sctp: clear new_transport when removing a peer sctp_process_asconf_param() stores a newly added peer transport in asoc->new_transport. After all parameters in the ASCONF chunk have been processed, sctp_sf_do_asconf() uses this pointer to send a HEARTBEAT to the new transport. An authenticated ASCONF from a remote SCTP peer can add a transport and remove it again with a wildcard DEL-IP parameter in the same chunk. The wildcard deletion preserves the transport on which the ASCONF arrived, but removes the newly added transport through sctp_assoc_del_nonprimary_peers(). The removal does not clear asoc->new_transport, leaving it pointing to the removed transport. sctp_sf_do_asconf() then creates a HEARTBEAT whose chunk->transport points to the removed transport without holding a transport reference. During local address replacement, src_out_of_asoc_ok keeps this HEARTBEAT on control_chunk_list. After the transport is freed by RCU, a successful ASCONF_ACK for the replacement address releases the queued HEARTBEAT and sctp_outq_select_transport() reads the freed transport's state. The issue was found during a static audit of SCTP objects. With an authenticated peer, the reproducer triggered the same KASAN report in 2 of 2 unpatched runs on a KASAN-enabled netdev/main kernel: BUG: KASAN: slab-use-after-free in sctp_outq_select_transport Read of size 4 at addr ffff88800b9bd95c by task python3/197 Call Trace: sctp_outq_select_transport+0x549/0x8b0 [sctp] sctp_outq_flush+0x306/0x2c60 [sctp] sctp_transport_immediate_rtx+0xaf/0x260 [sctp] sctp_process_asconf_ack+0xa48/0xf70 [sctp] Allocated by task 197: sctp_transport_new+0x68/0x650 [sctp] sctp_assoc_add_peer+0x258/0x12a0 [sctp] sctp_process_asconf+0x5e9/0x1090 [sctp] Last potentially related work creation: __call_rcu_common.constprop.0+0x77/0xb70 sctp_assoc_del_nonprimary_peers+0x7c/0xd0 [sctp] sctp_process_asconf+0xd9c/0x1090 [sctp] The first invalid access was a four-byte read of transport->state at net/sctp/outqueue.c:833. The same reproducer completed the full authenticated ASCONF and local-address replacement sequence with this change without a KASAN report or oops. Clear new_transport when its peer is removed, before it can be used to create the HEARTBEAT.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS

