Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
netfilter: ebtables: fix OOB read in compat_mtw_from_user
Luxiao Xu says:
The function compat_mtw_from_user() converts ebtables extensions from
32-bit user structures to kernel native structures. However, it lacks
proper validation of the user-supplied match_size/target_size.
When certain extensions are processed, the kernel-side translation
logic may perform memory accesses based on the extension's expected
size. If the user provides a size smaller than what the extension
requires, it results in an out-of-bounds read as reported by KASAN.
This fix introduces a check to ensure match_size is at least as large
as the extension's required compatsize. This covers matches, watchers,
and targets, while maintaining compatibility with standard targets.
AFAIU this is relevant for matches that need to go though
match->compat_from_user() call. Those that use plain memcpy with the
user-provided size are ok because the caller checks that size vs the
start of the next rule entry offset (which itself is checked vs. total
size copied from userspace).
The ->compat_from_user() callbacks assume they can read compatsize bytes,
so they need this extra check.
Based on an earlier patch from Luxiao Xu.
CVSS Score
7.8
EPSS Score
0.001
Published
2026-06-24
In the Linux kernel, the following vulnerability has been resolved:
af_unix: Reject SIOCATMARK on non-stream sockets
SIOCATMARK reports whether the receive queue is at the urgent mark for
MSG_OOB.
In AF_UNIX, MSG_OOB is supported only for SOCK_STREAM sockets.
SOCK_DGRAM and SOCK_SEQPACKET reject MSG_OOB in sendmsg() and recvmsg(),
so they should not support SIOCATMARK either.
Return -EOPNOTSUPP for non-stream sockets before checking the receive
queue.
CVSS Score
5.5
EPSS Score
0.002
Published
2026-06-24
In the Linux kernel, the following vulnerability has been resolved:
batman-adv: v: stop OGMv2 on disabled interface
When a batadv_hard_iface is disabled, its mesh_iface pointer is set to
NULL. However, batadv_v_ogm_send_meshif() may still dispatch OGMs via
batadv_v_ogm_queue_on_if() for interfaces that have since lost their
mesh_iface association. This results in a NULL pointer dereference when
batadv_v_ogm_queue_on_if() unconditionally calls netdev_priv() on the
now NULL hard_iface->mesh_iface to retrieve the batadv_priv.
It is necessary to ensure that the batadv_v_ogm_queue_on_if() checks that
it is using the same mesh_iface for which batadv_v_ogm_send_meshif() was
called.
CVSS Score
5.5
EPSS Score
0.002
Published
2026-06-24
In the Linux kernel, the following vulnerability has been resolved:
batman-adv: fix fragment reassembly length accounting
batman-adv keeps a running payload length for queued fragments and uses it
to validate a fragment chain before reassembly.
That accounting currently allows the accumulated fragment length to be
truncated during updates. As a result, malformed fragment chains can
bypass the intended validation and drive reassembly with inconsistent
length state, leading to a local denial of service.
Fix the accounting by storing the accumulated length in a length-typed
field and rejecting update overflows before the existing validation logic
runs.
The fix was verified against the original reproducer and against valid
fragment reassembly paths.
CVSS Score
9.8
EPSS Score
0.005
Published
2026-06-24
In the Linux kernel, the following vulnerability has been resolved:
netfilter: ip6t_hbh: reject oversized option lists
struct ip6t_opts stores at most IP6T_OPTS_OPTSNR option descriptors,
but hbh_mt6_check() does not reject larger optsnr values supplied from
userspace.
Validate optsnr in the rule setup path so only match data that fits the
fixed-size opts array can be installed. This follows the existing xtables
pattern of rejecting invalid user-provided counts in checkentry() and
keeps the packet matching path unchanged.
`struct ip6t_opts` has a fixed `opts[IP6T_OPTS_OPTSNR]` array,
where `IP6T_OPTS_OPTSNR` is 16, then off-by-one array access is possible:
[ 137.924693][ T8692] UBSAN: array-index-out-of-bounds in ../net/ipv6/netfilter/ip6t_hbh.c:110:29
[ 137.926167][ T8692] index 16 is out of range for type '__u16 [16]'
CVSS Score
7.1
EPSS Score
0.001
Published
2026-06-24
In the Linux kernel, the following vulnerability has been resolved:
batman-adv: frag: disallow unicast fragment in fragment
batadv_frag_skb_buffer() is called by batadv_batman_skb_recv() when a
BATADV_UNICAST_FRAG packet is received. Once all fragments are collected
and the packet is reassembled, batadv_recv_frag_packet() calls
batadv_batman_skb_recv() again to process the defragmented payload.
A malicious sender can craft a BATADV_UNICAST_FRAG packet whose reassembled
payload is itself a BATADV_UNICAST_FRAG packet (matryoshka-style nesting).
Each nesting level recurses through batadv_batman_skb_recv() without bound,
growing the kernel stack until it is exhausted.
Since refragmentation or fragments in fragments are not actually allowed,
discard all packets which are still BATADV_UNICAST_FRAG packets after the
defragmentation process.
CVSS Score
5.5
EPSS Score
0.002
Published
2026-06-24
In the Linux kernel, the following vulnerability has been resolved:
sctp: diag: reject stale associations in dump_one path
The SCTP exact sock_diag lookup can hold a transport reference, block on
lock_sock(sk), and then resume after sctp_association_free() has marked
the association dead and freed its bind address list.
When that happens, inet_assoc_attr_size() and
inet_diag_msg_sctpasoc_fill() can still dereference association state
that is no longer valid for reporting. In particular,
inet_diag_msg_sctpasoc_fill() may read an empty bind-address list as a
real sctp_sockaddr_entry and trigger an out-of-bounds read from
unrelated association memory.
Reject the association after taking the socket lock if it has been
reaped or detached from the endpoint, and report the lookup as stale.
This keeps the exact dump-one path from formatting torn association
state.
CVSS Score
7.1
EPSS Score
0.001
Published
2026-06-24
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: serialize accept_q access
bt_sock_poll() walks the accept queue without synchronization, while
child teardown can unlink the same socket and drop its last reference.
The unsynchronized accept queue walk has existed since the initial
Bluetooth import.
Protect accept_q with a dedicated lock for queue updates and polling.
Also rework bt_accept_dequeue() to take temporary child references under
the queue lock before dropping it and locking the child socket.
CVSS Score
8.8
EPSS Score
0.003
Published
2026-06-24
In the Linux kernel, the following vulnerability has been resolved:
batman-adv: fix tp_meter counter underflow during shutdown
batadv_tp_sender_shutdown() unconditionally decrements the "sending"
atomic counter. If multiple paths (e.g. timeout, user cancel, and
normal finish) call this function, the counter can underflow to -1.
Since the sender logic treats any non-zero value as "still sending",
a negative value causes the sender kthread to loop indefinitely.
This leads to a use-after-free when the interface is removed while
the zombie thread is still active.
Fix this by using atomic_xchg() to ensure the counter only transitions
from 1 to 0 once.
[sven: added missing change in batadv_tp_send]
CVSS Score
7.8
EPSS Score
0.001
Published
2026-06-24
In the Linux kernel, the following vulnerability has been resolved:
netfilter: xt_policy: fix strict mode inbound policy matching
match_policy_in() walks sec_path entries from the last transform to the
first one, but strict policy matching needs to consume info->pol[] in
the same forward order as the rule layout.
Derive the strict-match policy position from the number of transforms
already consumed so that multi-element inbound rules are matched
consistently.
CVSS Score
8.3
EPSS Score
0.003
Published
2026-06-24