CVE-2026-53362HIGH(7.8)
In the Linux kernel, the following vulnerability has been resolved:
ipv6: account for fraggap on the paged allocation path
In __ip6_append_data(), when the paged-allocation branch is taken
(MSG_MORE / NETIF_F_SG / large fraglen), alloclen and pagedlen are
computed as
alloclen = fragheaderlen + transhdrlen;
pagedlen = datalen - transhdrlen;
datalen already includes fraggap (datalen = length + fraggap). When
fraggap is non-zero, this is not the first skb and transhdrlen is zero.
The fraggap bytes carried over from the previous skb are copied just past
the fragment headers in the new skb's linear area. The linear area is
therefore undersized by fraggap bytes while pagedlen is overstated by the
same amount, and the copy writes past skb->end into the trailing
skb_shared_info.
An unprivileged user can trigger this via a UDPv6 socket using
MSG_MORE together with MSG_SPLICE_PAGES.
The bad accounting was introduced by commit 773ba4fe9104 ("ipv6:
avoid partial copy for zc"). Before commit ce650a166335 ("udp6: Fix
__ip6_append_data()'s handling of MSG_SPLICE_PAGES"), the negative
copy value caused -EINVAL to be returned. That later commit allowed
MSG_SPLICE_PAGES to proceed in this case, making the corruption
triggerable.
The non-paged branch sets alloclen to fraglen, which already accounts
for fraggap because datalen does. Bring the paged branch in line by
adding fraggap to alloclen and subtracting it from pagedlen.
After this adjustment, copy no longer collapses to -fraggap on the
paged path, so remove the stale comment describing that old arithmetic.
Since a negative copy is no longer expected for a valid MSG_SPLICE_PAGES
case, remove the MSG_SPLICE_PAGES exception from the negative copy check.
CVE-2024-56719CRITICAL(10.0)
EPSS 0.5%
In the Linux kernel, the following vulnerability has been resolved:
net: stmmac: fix TSO DMA API usage causing oops
Commit 66600fac7a98 ("net: stmmac: TSO: Fix unbalanced DMA map/unmap
for non-paged SKB data") moved the assignment of tx_skbuff_dma[]'s
members to be later in stmmac_tso_xmit().
The buf (dma cookie) and len stored in this structure are passed to
dma_unmap_single() by stmmac_tx_clean(). The DMA API requires that
the dma cookie passed to dma_unmap_single() is the same as the value
returned from dma_map_single(). However, by moving the assignment
later, this is not the case when priv->dma_cap.addr64 > 32 as "des"
is offset by proto_hdr_len.
This causes problems such as:
dwc-eth-dwmac 2490000.ethernet eth0: Tx DMA map failed
and with DMA_API_DEBUG enabled:
DMA-API: dwc-eth-dwmac 2490000.ethernet: device driver tries to +free DMA memory it has not allocated [device address=0x000000ffffcf65c0] [size=66 bytes]
Fix this by maintaining "des" as the original DMA cookie, and use
tso_des to pass the offset DMA cookie to stmmac_tso_allocator().
Full details of the crashes can be found at:
https://lore.kernel.org/all/d8112193-0386-4e14-b516-37c2d838171a@nvidia.com/
https://lore.kernel.org/all/klkzp5yn5kq5efgtrow6wbvnc46bcqfxs65nz3qy77ujr5turc@bwwhelz2l4dw/
CVE-2026-46195CRITICAL(9.8)
EPSS 0.7%
In the Linux kernel, the following vulnerability has been resolved:
smb: client: validate dacloffset before building DACL pointers
parse_sec_desc(), build_sec_desc(), and the chown path in
id_mode_to_cifs_acl() all add the server-supplied dacloffset to pntsd
before proving a DACL header fits inside the returned security
descriptor.
On 32-bit builds a malicious server can return dacloffset near
U32_MAX, wrap the derived DACL pointer below end_of_acl, and then slip
past the later pointer-based bounds checks. build_sec_desc() and
id_mode_to_cifs_acl() can then dereference DACL fields from the wrapped
pointer in the chmod/chown rewrite paths.
Validate dacloffset numerically before building any DACL pointer and
reuse the same helper at the three DACL entry points.
CVE-2025-21796CRITICAL(9.8)
EPSS 0.7%
In the Linux kernel, the following vulnerability has been resolved:
nfsd: clear acl_access/acl_default after releasing them
If getting acl_default fails, acl_access and acl_default will be released
simultaneously. However, acl_access will still retain a pointer pointing
to the released posix_acl, which will trigger a WARNING in
nfs3svc_release_getacl like this:
------------[ cut here ]------------
refcount_t: underflow; use-after-free.
WARNING: CPU: 26 PID: 3199 at lib/refcount.c:28
refcount_warn_saturate+0xb5/0x170
Modules linked in:
CPU: 26 UID: 0 PID: 3199 Comm: nfsd Not tainted
6.12.0-rc6-00079-g04ae226af01f-dirty #8
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
1.16.1-2.fc37 04/01/2014
RIP: 0010:refcount_warn_saturate+0xb5/0x170
Code: cc cc 0f b6 1d b3 20 a5 03 80 fb 01 0f 87 65 48 d8 00 83 e3 01 75
e4 48 c7 c7 c0 3b 9b 85 c6 05 97 20 a5 03 01 e8 fb 3e 30 ff <0f> 0b eb
cd 0f b6 1d 8a3
RSP: 0018:ffffc90008637cd8 EFLAGS: 00010282
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff83904fde
RDX: dffffc0000000000 RSI: 0000000000000008 RDI: ffff88871ed36380
RBP: ffff888158beeb40 R08: 0000000000000001 R09: fffff520010c6f56
R10: ffffc90008637ab7 R11: 0000000000000001 R12: 0000000000000001
R13: ffff888140e77400 R14: ffff888140e77408 R15: ffffffff858b42c0
FS: 0000000000000000(0000) GS:ffff88871ed00000(0000)
knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000562384d32158 CR3: 000000055cc6a000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
? refcount_warn_saturate+0xb5/0x170
? __warn+0xa5/0x140
? refcount_warn_saturate+0xb5/0x170
? report_bug+0x1b1/0x1e0
? handle_bug+0x53/0xa0
? exc_invalid_op+0x17/0x40
? asm_exc_invalid_op+0x1a/0x20
? tick_nohz_tick_stopped+0x1e/0x40
? refcount_warn_saturate+0xb5/0x170
? refcount_warn_saturate+0xb5/0x170
nfs3svc_release_getacl+0xc9/0xe0
svc_process_common+0x5db/0xb60
? __pfx_svc_process_common+0x10/0x10
? __rcu_read_unlock+0x69/0xa0
? __pfx_nfsd_dispatch+0x10/0x10
? svc_xprt_received+0xa1/0x120
? xdr_init_decode+0x11d/0x190
svc_process+0x2a7/0x330
svc_handle_xprt+0x69d/0x940
svc_recv+0x180/0x2d0
nfsd+0x168/0x200
? __pfx_nfsd+0x10/0x10
kthread+0x1a2/0x1e0
? kthread+0xf4/0x1e0
? __pfx_kthread+0x10/0x10
ret_from_fork+0x34/0x60
? __pfx_kthread+0x10/0x10
ret_from_fork_asm+0x1a/0x30
</TASK>
Kernel panic - not syncing: kernel: panic_on_warn set ...
Clear acl_access/acl_default after posix_acl_release is called to prevent
UAF from being triggered.
CVE-2026-43493CRITICAL(9.8)
EPSS 0.6%
In the Linux kernel, the following vulnerability has been resolved:
crypto: pcrypt - Fix handling of MAY_BACKLOG requests
MAY_BACKLOG requests can return EBUSY. Handle them by checking
for that value and filtering out EINPROGRESS notifications.
CVE-2026-31637CRITICAL(9.8)
EPSS 0.6%
In the Linux kernel, the following vulnerability has been resolved:
rxrpc: reject undecryptable rxkad response tickets
rxkad_decrypt_ticket() decrypts the RXKAD response ticket and then
parses the buffer as plaintext without checking whether
crypto_skcipher_decrypt() succeeded.
A malformed RESPONSE can therefore use a non-block-aligned ticket
length, make the decrypt operation fail, and still drive the ticket
parser with attacker-controlled bytes.
Check the decrypt result and abort the connection with RXKADBADTICKET
when ticket decryption fails.
CVE-2026-53221CRITICAL(9.8)
EPSS 0.6%
In the Linux kernel, the following vulnerability has been resolved:
ip6_vti: fix incorrect tunnel matching in vti6_tnl_lookup()
In vti6_tnl_lookup(), when an exact match for a tunnel fails,
the code falls back to searching for wildcard tunnels:
- Tunnels matching the packet's local address, with any remote address
wildcard remote).
- Tunnels matching the packet's remote address, with any local address
(wildcard local).
However, vti6 stores all these different types of tunnels in the same
hash table (ip6n->tnls_r_l) prone to hash collisions.
The bug is that the fallback search loops in vti6_tnl_lookup() were
missing checks to ensure that the candidate tunnel actually has
a wildcard address.
CVE-2026-53228CRITICAL(9.8)
EPSS 0.6%
In the Linux kernel, the following vulnerability has been resolved:
ipv6: sit: reload inner IPv6 header after GSO offloads
ipip6_tunnel_xmit() caches the inner IPv6 header pointer at function
entry and continues using it after iptunnel_handle_offloads().
For GSO skbs, iptunnel_handle_offloads() calls skb_header_unclone().
When the skb header is cloned, skb_header_unclone() can call
pskb_expand_head(), which may move the skb head. The pskb_expand_head()
contract requires pointers into the skb header to be reloaded after the
call.
If the later skb_realloc_headroom() branch is not taken, SIT uses the
stale iph6 pointer to read the inner hop limit and DS field. That can
read from a freed skb head after the old head's remaining clone is
released.
Reload iph6 after the offload helper succeeds and before subsequent
reads from the inner IPv6 header. Keep the existing reload after
skb_realloc_headroom(), since that branch can also replace the skb.
CVE-2025-21707CRITICAL(9.8)
EPSS 0.5%
In the Linux kernel, the following vulnerability has been resolved:
mptcp: consolidate suboption status
MPTCP maintains the received sub-options status is the bitmask carrying
the received suboptions and in several bitfields carrying per suboption
additional info.
Zeroing the bitmask before parsing is not enough to ensure a consistent
status, and the MPTCP code has to additionally clear some bitfiled
depending on the actually parsed suboption.
The above schema is fragile, and syzbot managed to trigger a path where
a relevant bitfield is not cleared/initialized:
BUG: KMSAN: uninit-value in __mptcp_expand_seq net/mptcp/options.c:1030 [inline]
BUG: KMSAN: uninit-value in mptcp_expand_seq net/mptcp/protocol.h:864 [inline]
BUG: KMSAN: uninit-value in ack_update_msk net/mptcp/options.c:1060 [inline]
BUG: KMSAN: uninit-value in mptcp_incoming_options+0x2036/0x3d30 net/mptcp/options.c:1209
__mptcp_expand_seq net/mptcp/options.c:1030 [inline]
mptcp_expand_seq net/mptcp/protocol.h:864 [inline]
ack_update_msk net/mptcp/options.c:1060 [inline]
mptcp_incoming_options+0x2036/0x3d30 net/mptcp/options.c:1209
tcp_data_queue+0xb4/0x7be0 net/ipv4/tcp_input.c:5233
tcp_rcv_established+0x1061/0x2510 net/ipv4/tcp_input.c:6264
tcp_v4_do_rcv+0x7f3/0x11a0 net/ipv4/tcp_ipv4.c:1916
tcp_v4_rcv+0x51df/0x5750 net/ipv4/tcp_ipv4.c:2351
ip_protocol_deliver_rcu+0x2a3/0x13d0 net/ipv4/ip_input.c:205
ip_local_deliver_finish+0x336/0x500 net/ipv4/ip_input.c:233
NF_HOOK include/linux/netfilter.h:314 [inline]
ip_local_deliver+0x21f/0x490 net/ipv4/ip_input.c:254
dst_input include/net/dst.h:460 [inline]
ip_rcv_finish+0x4a2/0x520 net/ipv4/ip_input.c:447
NF_HOOK include/linux/netfilter.h:314 [inline]
ip_rcv+0xcd/0x380 net/ipv4/ip_input.c:567
__netif_receive_skb_one_core net/core/dev.c:5704 [inline]
__netif_receive_skb+0x319/0xa00 net/core/dev.c:5817
process_backlog+0x4ad/0xa50 net/core/dev.c:6149
__napi_poll+0xe7/0x980 net/core/dev.c:6902
napi_poll net/core/dev.c:6971 [inline]
net_rx_action+0xa5a/0x19b0 net/core/dev.c:7093
handle_softirqs+0x1a0/0x7c0 kernel/softirq.c:561
__do_softirq+0x14/0x1a kernel/softirq.c:595
do_softirq+0x9a/0x100 kernel/softirq.c:462
__local_bh_enable_ip+0x9f/0xb0 kernel/softirq.c:389
local_bh_enable include/linux/bottom_half.h:33 [inline]
rcu_read_unlock_bh include/linux/rcupdate.h:919 [inline]
__dev_queue_xmit+0x2758/0x57d0 net/core/dev.c:4493
dev_queue_xmit include/linux/netdevice.h:3168 [inline]
neigh_hh_output include/net/neighbour.h:523 [inline]
neigh_output include/net/neighbour.h:537 [inline]
ip_finish_output2+0x187c/0x1b70 net/ipv4/ip_output.c:236
__ip_finish_output+0x287/0x810
ip_finish_output+0x4b/0x600 net/ipv4/ip_output.c:324
NF_HOOK_COND include/linux/netfilter.h:303 [inline]
ip_output+0x15f/0x3f0 net/ipv4/ip_output.c:434
dst_output include/net/dst.h:450 [inline]
ip_local_out net/ipv4/ip_output.c:130 [inline]
__ip_queue_xmit+0x1f2a/0x20d0 net/ipv4/ip_output.c:536
ip_queue_xmit+0x60/0x80 net/ipv4/ip_output.c:550
__tcp_transmit_skb+0x3cea/0x4900 net/ipv4/tcp_output.c:1468
tcp_transmit_skb net/ipv4/tcp_output.c:1486 [inline]
tcp_write_xmit+0x3b90/0x9070 net/ipv4/tcp_output.c:2829
__tcp_push_pending_frames+0xc4/0x380 net/ipv4/tcp_output.c:3012
tcp_send_fin+0x9f6/0xf50 net/ipv4/tcp_output.c:3618
__tcp_close+0x140c/0x1550 net/ipv4/tcp.c:3130
__mptcp_close_ssk+0x74e/0x16f0 net/mptcp/protocol.c:2496
mptcp_close_ssk+0x26b/0x2c0 net/mptcp/protocol.c:2550
mptcp_pm_nl_rm_addr_or_subflow+0x635/0xd10 net/mptcp/pm_netlink.c:889
mptcp_pm_nl_rm_subflow_received net/mptcp/pm_netlink.c:924 [inline]
mptcp_pm_flush_addrs_and_subflows net/mptcp/pm_netlink.c:1688 [inline]
mptcp_nl_flush_addrs_list net/mptcp/pm_netlink.c:1709 [inline]
mptcp_pm_nl_flush_addrs_doit+0xe10/0x1630 net/mptcp/pm_netlink.c:1750
genl_family_rcv_msg_doit net/netlink/genetlink.c:1115 [inline]
---truncated---
CVE-2026-46137CRITICAL(9.8)
EPSS 0.5%
In the Linux kernel, the following vulnerability has been resolved:
mptcp: pm: ADD_ADDR rtx: fix potential data-race
This mptcp_pm_add_timer() helper is executed as a timer callback in
softirq context. To avoid any data races, the socket lock needs to be
held with bh_lock_sock().
If the socket is in use, retry again soon after, similar to what is done
with the keepalive timer.
CVE-2026-31705CRITICAL(9.8)
EPSS 0.4%
In the Linux kernel, the following vulnerability has been resolved:
ksmbd: fix out-of-bounds write in smb2_get_ea() EA alignment
smb2_get_ea() applies 4-byte alignment padding via memset() after
writing each EA entry. The bounds check on buf_free_len is performed
before the value memcpy, but the alignment memset fires unconditionally
afterward with no check on remaining space.
When the EA value exactly fills the remaining buffer (buf_free_len == 0
after value subtraction), the alignment memset writes 1-3 NUL bytes
past the buf_free_len boundary. In compound requests where the response
buffer is shared across commands, the first command (e.g., READ) can
consume most of the buffer, leaving a tight remainder for the QUERY_INFO
EA response. The alignment memset then overwrites past the physical
kvmalloc allocation into adjacent kernel heap memory.
Add a bounds check before the alignment memset to ensure buf_free_len
can accommodate the padding bytes.
This is the same bug pattern fixed by commit beef2634f81f ("ksmbd: fix
potencial OOB in get_file_all_info() for compound requests") and
commit fda9522ed6af ("ksmbd: fix OOB write in QUERY_INFO for compound
requests"), both of which added bounds checks before unconditional
writes in QUERY_INFO response handlers.
CVE-2026-53131CRITICAL(9.4)
EPSS 0.4%
In the Linux kernel, the following vulnerability has been resolved:
netfilter: require Ethernet MAC header before using eth_hdr()
`ip6t_eui64`, `xt_mac`, the `bitmap:ip,mac`, `hash:ip,mac`, and
`hash:mac` ipset types, and `nf_log_syslog` access `eth_hdr(skb)`
after either assuming that the skb is associated with an Ethernet
device or checking only that the `ETH_HLEN` bytes at
`skb_mac_header(skb)` lie between `skb->head` and `skb->data`.
Make these paths first verify that the skb is associated with an
Ethernet device, that the MAC header was set, and that it spans at
least a full Ethernet header before accessing `eth_hdr(skb)`.