Linux: >> Linux Kernel >> 4.14.284 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
net/packet: fix TOCTOU race on mmap'd vnet_hdr in tpacket_snd()
In tpacket_snd(), when PACKET_VNET_HDR is enabled, vnet_hdr points
directly into the mmap'd TX ring buffer shared with userspace. The
kernel validates the header via __packet_snd_vnet_parse() but then
re-reads all fields later in virtio_net_hdr_to_skb(). A concurrent
userspace thread can modify the vnet_hdr fields between validation
and use, bypassing all safety checks.
The non-TPACKET path (packet_snd()) already correctly copies vnet_hdr
to a stack-local variable. All other vnet_hdr consumers in the kernel
(tun.c, tap.c, virtio_net.c) also use stack copies. The TPACKET TX
path is the only caller of virtio_net_hdr_to_skb() that reads directly
from user-controlled shared memory.
Fix this by copying vnet_hdr from the mmap'd ring buffer to a
stack-local variable before validation and use, consistent with the
approach used in packet_snd() and all other callers.
CVSS Score
7.8
EPSS Score
0.001
Published
2026-05-01
In the Linux kernel, the following vulnerability has been resolved:
xen/privcmd: fix double free via VMA splitting
privcmd_vm_ops defines .close (privcmd_close), but neither .may_split
nor .open. When userspace does a partial munmap() on a privcmd mapping,
the kernel splits the VMA via __split_vma(). Since may_split is NULL,
the split is allowed. vm_area_dup() copies vm_private_data (a pages
array allocated in alloc_empty_pages()) into the new VMA without any
fixup, because there is no .open callback.
Both VMAs now point to the same pages array. When the unmapped portion
is closed, privcmd_close() calls:
- xen_unmap_domain_gfn_range()
- xen_free_unpopulated_pages()
- kvfree(pages)
The surviving VMA still holds the dangling pointer. When it is later
destroyed, the same sequence runs again, which leads to a double free.
Fix this issue by adding a .may_split callback denying the VMA split.
This is XSA-487 / CVE-2026-31787
CVSS Score
7.8
EPSS Score
0.002
Published
2026-04-30
In the Linux kernel, the following vulnerability has been resolved:
rtnetlink: add missing netlink_ns_capable() check for peer netns
rtnl_newlink() lacks a CAP_NET_ADMIN capability check on the peer
network namespace when creating paired devices (veth, vxcan,
netkit). This allows an unprivileged user with a user namespace
to create interfaces in arbitrary network namespaces, including
init_net.
Add a netlink_ns_capable() check for CAP_NET_ADMIN in the peer
namespace before allowing device creation to proceed.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-04-30
In the Linux kernel, the following vulnerability has been resolved:
Buffer overflow in drivers/xen/sys-hypervisor.c
The build id returned by HYPERVISOR_xen_version(XENVER_build_id) is
neither NUL terminated nor a string.
The first causes a buffer overflow as sprintf in buildid_show will
read and copy till it finds a NUL.
00000000 f4 91 51 f4 dd 38 9e 9d 65 47 52 eb 10 71 db 50 |..Q..8..eGR..q.P|
00000010 b9 a8 01 42 6f 2e 32 |...Bo.2|
00000017
So use a memcpy instead of sprintf to have the correct value:
00000000 f4 91 51 f4 dd 00 9e 9d 65 47 52 eb 10 71 db 50 |..Q.....eGR..q.P|
00000010 b9 a8 01 42 |...B|
00000014
(the above have a hack to embed a zero inside and check it's
returned correctly).
This is XSA-485 / CVE-2026-31786
CVSS Score
7.8
EPSS Score
0.002
Published
2026-04-30
In the Linux kernel, the following vulnerability has been resolved:
gpio: omap: do not register driver in probe()
Commit 11a78b794496 ("ARM: OMAP: MPUIO wake updates") registers the
omap_mpuio_driver from omap_mpuio_init(), which is called from
omap_gpio_probe().
However, it neither makes sense to register drivers from probe()
callbacks of other drivers, nor does the driver core allow registering
drivers with a device lock already being held.
The latter was revealed by commit dc23806a7c47 ("driver core: enforce
device_lock for driver_match_device()") leading to a potential deadlock
condition described in [1].
Additionally, the omap_mpuio_driver is never unregistered from the
driver core, even if the module is unloaded.
Hence, register the omap_mpuio_driver from the module initcall and
unregister it in module_exit().
CVSS Score
5.5
EPSS Score
0.001
Published
2026-04-27
In the Linux kernel, the following vulnerability has been resolved:
batman-adv: avoid OGM aggregation when skb tailroom is insufficient
When OGM aggregation state is toggled at runtime, an existing forwarded
packet may have been allocated with only packet_len bytes, while a later
packet can still be selected for aggregation. Appending in this case can
hit skb_put overflow conditions.
Reject aggregation when the target skb tailroom cannot accommodate the new
packet. The caller then falls back to creating a new forward packet
instead of appending.
CVSS Score
7.8
EPSS Score
0.001
Published
2026-04-25
In the Linux kernel, the following vulnerability has been resolved:
netfilter: ip6t_eui64: reject invalid MAC header for all packets
`eui64_mt6()` derives a modified EUI-64 from the Ethernet source address
and compares it with the low 64 bits of the IPv6 source address.
The existing guard only rejects an invalid MAC header when
`par->fragoff != 0`. For packets with `par->fragoff == 0`, `eui64_mt6()`
can still reach `eth_hdr(skb)` even when the MAC header is not valid.
Fix this by removing the `par->fragoff != 0` condition so that packets
with an invalid MAC header are rejected before accessing `eth_hdr(skb)`.
CVSS Score
9.4
EPSS Score
0.003
Published
2026-04-25
In the Linux kernel, the following vulnerability has been resolved:
net/sched: sch_netem: fix out-of-bounds access in packet corruption
In netem_enqueue(), the packet corruption logic uses
get_random_u32_below(skb_headlen(skb)) to select an index for
modifying skb->data. When an AF_PACKET TX_RING sends fully non-linear
packets over an IPIP tunnel, skb_headlen(skb) evaluates to 0.
Passing 0 to get_random_u32_below() takes the variable-ceil slow path
which returns an unconstrained 32-bit random integer. Using this
unconstrained value as an offset into skb->data results in an
out-of-bounds memory access.
Fix this by verifying skb_headlen(skb) is non-zero before attempting
to corrupt the linear data area. Fully non-linear packets will silently
bypass the corruption logic.
CVSS Score
7.8
EPSS Score
0.001
Published
2026-04-25
In the Linux kernel, the following vulnerability has been resolved:
rxrpc: only handle RESPONSE during service challenge
Only process RESPONSE packets while the service connection is still in
RXRPC_CONN_SERVICE_CHALLENGING. Check that state under state_lock before
running response verification and security initialization, then use a local
secured flag to decide whether to queue the secured-connection work after
the state transition. This keeps duplicate or late RESPONSE packets from
re-running the setup path and removes the unlocked post-transition state
test.
CVSS Score
7.5
EPSS Score
0.004
Published
2026-04-25
In the Linux kernel, the following vulnerability has been resolved:
crypto: af_alg - limit RX SG extraction by receive buffer budget
Make af_alg_get_rsgl() limit each RX scatterlist extraction to the
remaining receive buffer budget.
af_alg_get_rsgl() currently uses af_alg_readable() only as a gate
before extracting data into the RX scatterlist. Limit each extraction
to the remaining af_alg_rcvbuf(sk) budget so that receive-side
accounting matches the amount of data attached to the request.
If skcipher cannot obtain enough RX space for at least one chunk while
more data remains to be processed, reject the recvmsg call instead of
rounding the request length down to zero.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-04-25