Linux: >> Linux Kernel >> 6.12.53 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
net: mvpp2: refill RX buffers before XDP or skb use
The RX error path returns the current descriptor buffer to the hardware
BM pool. That is only valid while the driver still owns the buffer.
mvpp2_rx_refill() can fail after the current buffer has been handed to
XDP or attached to an skb. In those cases mvpp2_run_xdp() may have
recycled, redirected, or queued the page for XDP_TX, and an skb free also
retires the data buffer. Returning such a buffer to BM lets hardware DMA
into memory that is no longer owned by the RX ring.
Refill the BM pool before handing the current buffer to XDP or to the
skb. If the allocation fails there, drop the packet and return the
still-owned current buffer to BM, preserving the pool depth. Once the
refill succeeds, later local drops retire/free the current buffer instead
of returning it to BM.
CVSS Score
9.8
EPSS Score
0.005
Published
2026-06-25
In the Linux kernel, the following vulnerability has been resolved:
net: mvpp2: limit XDP frame size to the RX buffer
mvpp2 has short and long BM pools, and short pool buffers can be smaller
than PAGE_SIZE. The XDP path nevertheless initializes every xdp_buff with
PAGE_SIZE as frame size.
XDP helpers use frame_sz to validate tail growth and to derive the hard
end of the data area. Advertising PAGE_SIZE for short buffers can let
bpf_xdp_adjust_tail() grow a packet past the real allocation, corrupting
memory or later tripping skb tailroom checks.
Initialize the XDP buffer with bm_pool->frag_size so XDP tailroom matches
the actual buffer backing the packet.
CVSS Score
9.8
EPSS Score
0.005
Published
2026-06-25
In the Linux kernel, the following vulnerability has been resolved:
net: mvpp2: sync RX data at the hardware packet offset
mvpp2 programs the RX queue packet offset, so hardware writes received
data at dma_addr + MVPP2_SKB_HEADROOM. The current CPU sync starts at
dma_addr and only covers rx_bytes + MVPP2_MH_SIZE bytes, which syncs the
unused headroom and misses the same number of bytes at the packet tail.
On non-coherent DMA systems this can leave the CPU reading stale cache
contents for the end of the received frame.
Use dma_sync_single_range_for_cpu() with MVPP2_SKB_HEADROOM as the range
offset so the sync covers the Marvell header and packet data actually
written by hardware.
CVSS Score
8.6
EPSS Score
0.004
Published
2026-06-25
In the Linux kernel, the following vulnerability has been resolved:
netfilter: nft_exthdr: fix register tracking for F_PRESENT flag
nft_exthdr_init() passes user-controlled priv->len to
nft_parse_register_store(), which marks that many bytes in the
register bitmap as initialized. However, when NFT_EXTHDR_F_PRESENT
is set, the eval paths write only 1 byte (nft_reg_store8) or
4 bytes (*dest = 0 on TCP/DCCP error path). When len > 4,
registers beyond the first are never written, retaining
uninitialized stack data from nft_regs.
Bail out if userspace requests too much data when F_PRESENT is set.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-06-25
In the Linux kernel, the following vulnerability has been resolved:
netfilter: x_tables: avoid leaking percpu counter pointers
The native and compat get-entries paths copy the fixed rule entry header
from the kernelized rule blob to userspace before overwriting the entry's
counter fields with a sanitized counter snapshot.
On SMP kernels, entry->counters.pcnt contains the percpu allocation
address used by x_tables rule counters. A caller can provide a userspace
buffer that faults during the initial fixed-header copy after pcnt has
been copied but before the later sanitized counter copy runs. The syscall
then returns -EFAULT while leaving the raw percpu pointer in userspace.
Copy only the fixed entry prefix before counters from the kernelized rule
blob, then copy the sanitized counter snapshot into the counter field.
Apply this ordering to the IPv4, IPv6, and ARP native and compat
get-entries implementations so a fault cannot expose the internal percpu
counter pointer.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-06-25
In the Linux kernel, the following vulnerability has been resolved:
netfilter: revalidate bridge ports
ebt_redirect_tg() dereferences br_port_get_rcu() return without a
NULL check, causing a kernel panic when the bridge port has been
removed between the original hook invocation and an NFQUEUE
reinject.
A mere NULL check isn't sufficient, however. As sashiko review
points out userspace can not only remove the port from the bridge,
it could also place the device in a different virtual device, e.g.
macvlan.
If this happens, we must drop the packet, there is no way for us to
reinject it into the bridge path.
Switch to _upper API, we don't need the bridge port structure.
Also, this fix keeps another bug intact:
Both nfnetlink_log and nfnetlink_queue use CONFIG_BRIDGE_NETFILTER
too aggressive, which prevents certain logging features when queueing
in bridge family: NETFILTER_FAMILY_BRIDGE can be enabled while the old
CONFIG_BRIDGE_NETFILTER cruft is off.
Fixes tag is a common ancestor, this was always broken.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-06-25
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.
CVSS Score
9.8
EPSS Score
0.006
Published
2026-06-25
In the Linux kernel, the following vulnerability has been resolved:
accel/ivpu: Add bounds checks for firmware log indices
Add validation that read and write indices in the firmware log buffer
are within valid bounds (< data_size) before using them. If
out-of-bounds indices are encountered (from firmware), clamp them to
safe values instead of proceeding with invalid offsets.
This prevents potential out-of-bounds buffer access when firmware
supplies invalid log indices.
CVSS Score
7.1
EPSS Score
0.001
Published
2026-06-25
In the Linux kernel, the following vulnerability has been resolved:
mm/memory-failure: fix hugetlb_lock AA deadlock in get_huge_page_for_hwpoison
Two concurrent madvise(MADV_HWPOISON) calls on the same hugetlb page can
trigger a recursive spinlock self-deadlock (AA deadlock) on hugetlb_lock
when racing with a concurrent unmap:
thread#0 thread#1
-------- --------
madvise(folio, MADV_HWPOISON)
-> poisons the folio successfully
madvise(folio, MADV_HWPOISON) unmap(folio)
try_memory_failure_hugetlb
get_huge_page_for_hwpoison
spin_lock_irq(&hugetlb_lock) <- held
__get_huge_page_for_hwpoison
hugetlb_update_hwpoison()
-> MF_HUGETLB_FOLIO_PRE_POISONED
goto out:
folio_put()
refcount: 1 -> 0
free_huge_folio()
spin_lock_irqsave(&hugetlb_lock)
-> AA DEADLOCK!
The out: path in __get_huge_page_for_hwpoison() calls folio_put() to drop
the GUP reference while the hugetlb_lock is still held by the hugetlb.c
wrapper get_huge_page_for_hwpoison(). If concurrent unmap has released
the page table mapping reference, folio_put() drops the folio refcount to
zero, triggering free_huge_folio() which attempts to re-acquire the
non-recursive hugetlb_lock.
Fix this by moving hugetlb_lock acquisition from the hugetlb.c wrapper
into get_huge_page_for_hwpoison(). Place spin_unlock_irq() before the
folio_put() at the out: label so the folio is always released outside the
lock.
[akpm@linux-foundation.org: fix race, rename label per Miaohe]
CVSS Score
5.5
EPSS Score
0.001
Published
2026-06-25
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: L2CAP: reject BR/EDR signaling packets over MTUsig
net/bluetooth/l2cap_core.c:l2cap_sig_channel() accepts BR/EDR
signaling packets up to the channel MTU and dispatches each command
without enforcing the signaling MTU (MTUsig). A Bluetooth BR/EDR peer
within radio range can send a fixed-channel CID 0x0001 packet that is
larger than MTUsig and contains many L2CAP_ECHO_REQ commands before
pairing. In a real-radio stock-kernel run, one 681-byte signaling
packet containing 168 zero-length ECHO_REQ commands made the target
transmit 168 ECHO_RSP frames over about 220 ms.
Impact: a Bluetooth BR/EDR peer within radio range, before pairing, can
force 168 ECHO_RSP frames from one 681-byte fixed-channel signaling
packet containing packed ECHO_REQ commands.
Define Linux's BR/EDR signaling MTU as the spec minimum of 48 bytes and
reject any larger signaling packet with one L2CAP_COMMAND_REJECT_RSP
carrying L2CAP_REJ_MTU_EXCEEDED before any command is dispatched.
The Bluetooth Core spec wording for MTUExceeded says the reject
identifier shall match the first request command in the packet, and
that packets containing only responses shall be silently discarded.
Linux intentionally deviates from that prescription: silently
discarding desynchronizes the peer because the remote stack never
learns its responses were dropped, and locating the first request
command requires walking command headers past MTUsig, i.e. processing
bytes from a packet we have already decided is too large to process.
We therefore always emit one reject and use the identifier from the
first command header, a single fixed-offset byte read.
The unrestricted BR/EDR signaling parser and ECHO_REQ response path both
trace to the initial git import; no later introducing commit is
available for a Fixes tag.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-06-25