Linux: >> Linux Kernel >> 6.12.54 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
sctp: validate cached peer INIT chunk length in COOKIE_ECHO processing
When a listening SCTP server processes a COOKIE_ECHO chunk, the cached
peer INIT chunk embedded after the cookie is parsed and its parameters
are later walked by sctp_process_init() using sctp_walk_params().
However, the chunk header length of this cached INIT chunk was not
validated against the remaining buffer in the COOKIE_ECHO payload. If
the length field is inflated, the parameter walk can run beyond the
actual received data, leading to out-of-bounds reads and potential
memory corruption during later parameter handling (e.g. STATE_COOKIE
processing and kmemdup() copies).
Add a bounds check in sctp_unpack_cookie() to ensure the cached INIT
chunk length does not exceed the available data in the COOKIE_ECHO
buffer before it is used.
CVSS Score
9.8
EPSS Score
0.005
Published
2026-06-25
In the Linux kernel, the following vulnerability has been resolved:
net: ethernet: mtk_eth_soc: Fix use-after-free in metadata dst teardown
mtk_free_dev() calls metadata_dst_free() which frees the metadata_dst
with kfree() immediately, bypassing the RCU grace period.
In the RX path, skb_dst_set_noref() sets a non-refcounted pointer from
the skb to the metadata_dst. This function requires RCU read-side
protection and the dst must remain valid until all RCU readers complete.
Since metadata_dst_free() calls kfree() directly, a use-after-free can
occur if any skb still holds a noref pointer to the dst when the driver
tears it down.
Replace metadata_dst_free() with dst_release() which properly goes
through the refcount path: when the refcount drops to zero, it schedules
the actual free via call_rcu_hurry(), ensuring all RCU readers have
completed before the memory is freed.
CVSS Score
9.8
EPSS Score
0.005
Published
2026-06-25
In the Linux kernel, the following vulnerability has been resolved:
ipv4: restrict IPOPT_SSRR and IPOPT_LSRR options
This patch restricts setting Loose Source and Record Route (LSRR)
and Strict Source and Record Route (SSRR) IP options to users
with CAP_NET_RAW capability.
This prevents unprivileged applications from forcing packets to route
through attacker-controlled nodes to leak TCP ISN and possibly other
protocol information.
While LSRR and SSRR are commonly filtered in many network environments,
they may still be supported and forwarded along some network paths.
RFC 7126 (Recommendations on Filtering of IPv4 Packets Containing
IPv4 Options) recommend to drop these options in 4.3 and 4.4.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-06-25
In the Linux kernel, the following vulnerability has been resolved:
xsk: cache csum_start/csum_offset to fix TOCTOU in xsk_skb_metadata()
The TX metadata area resides in the UMEM buffer which is memory-mapped
and concurrently writable by userspace. In xsk_skb_metadata(),
csum_start and csum_offset are read from shared memory for bounds
validation, then read again for skb assignment. A malicious userspace
application can race to overwrite these values between the two reads,
bypassing the bounds check and causing out-of-bounds memory access
during checksum computation in the transmit path.
Fix this by reading csum_start and csum_offset into local variables
once, then using the local copies for both validation and assignment.
Note that other metadata fields (flags, launch_time) and the cached
csum fields may be mutually inconsistent due to concurrent userspace
writes, but this is benign: the only security-critical invariant is
that each field's validated value is the same one used, which local
caching guarantees.
CVSS Score
7.8
EPSS Score
0.001
Published
2026-06-25
In the Linux kernel, the following vulnerability has been resolved:
net: phy: clean the sfp upstream if phy probing fails
Sashiko reported that we don't call sfp_bus_del_upstream() in the probe
failure path, so let's add it, otherwise the sfp-bus is left with a
dangling 'upstream' field, that may be used later on during SFP events.
This issue existed before the generic phylib sfp support, back when
drivers were calling phy_sfp_probe themselves.
CVSS Score
8.8
EPSS Score
0.002
Published
2026-06-25
In the Linux kernel, the following vulnerability has been resolved:
netdev: fix double-free in netdev_nl_bind_rx_doit()
Sashiko flags that genlmsg_reply() always consumes the skb.
The error path calls nlmsg_free(rsp) so we can't jump directly
to it. Let's not unbind, just propagate the error to the user.
This is the typical way of handling genlmsg_reply() failures.
They shouldn't happen unless user does something silly like
calling the kernel with an already-full rcvbuf.
CVSS Score
7.8
EPSS Score
0.001
Published
2026-06-25
In the Linux kernel, the following vulnerability has been resolved:
net: ibm: emac: Fix use-after-free during device removal
The driver was using devm_register_netdev() which causes unregister_netdev()
to be deferred until the devres cleanup phase, which runs after emac_remove()
returns. This creates a use-after-free window where:
1. emac_remove() is called, which tears down hardware (cancels work, detaches
modules, unregisters from MAL)
2. emac_remove() returns
3. devres cleanup runs and finally calls unregister_netdev()
During step 3, the network stack might still process packets, triggering
emac_irq(), emac_poll(), or other handlers that access now-freed hardware
resources (dev->emacp, dev->mal, etc.).
Fix this by replacing devm_register_netdev() with manual register_netdev()
and calling unregister_netdev() at the beginning of emac_remove(), before
any hardware teardown. This ensures the network device is fully stopped and
unregistered before hardware resources are released.
The change is safe because:
- dev->ndev is assigned very early in probe (before any error paths that
could bypass emac_remove)
- platform_set_drvdata() is only called after successful registration, so
emac_remove() only runs for fully registered devices
- unregister_netdev() is idempotent and safe to call on any registered device
CVSS Score
7.8
EPSS Score
0.001
Published
2026-06-25
In the Linux kernel, the following vulnerability has been resolved:
net: add pskb_may_pull() to skb_gro_receive_list()
skb_gro_receive_list() calls skb_pull(skb, skb_gro_offset(skb)) without
first ensuring the data is in the linear area via pskb_may_pull(). When
the skb arrives via napi_gro_frags(), skb_headlen can be 0 (all data in
page fragments) while skb_gro_offset is non-zero (after IP+TCP header
parsing). The skb_pull() then decrements skb->len by skb_gro_offset
but skb->data_len stays unchanged, hitting BUG_ON(skb->len < skb->data_len)
in __skb_pull().
The UDP fraglist GRO path already contains this guard at
udp_offload.c:749. Adding it to skb_gro_receive_list() itself provides
centralized protection for all callers (TCP, UDP, and any future
protocols), and ensures the precondition of skb_pull() is satisfied
before it is called.
On pskb_may_pull() failure, set NAPI_GRO_CB(skb)->flush = 1 so the
skb is not held as a new GRO head and is instead delivered through the
normal receive path, matching the UDP handling.
CVSS Score
7.5
EPSS Score
0.005
Published
2026-06-25
In the Linux kernel, the following vulnerability has been resolved:
tcp: restrict SO_ATTACH_FILTER to priv users
This patch restricts the use of SO_ATTACH_FILTER (cBPF) on TCP sockets
to users with CAP_NET_ADMIN capability.
This blocks potential side-channel attack where an unprivileged application
attaches a filter to leak TCP sequence/acknowledgment numbers.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-06-25
In the Linux kernel, the following vulnerability has been resolved:
gpio: mvebu: fix NULL pointer dereference in suspend/resume
mvebu_pwm_suspend() and mvebu_pwm_resume() are called for all GPIO
banks during suspend/resume, but not all banks have PWM functionality.
GPIO banks without PWM have mvchip->mvpwm set to NULL.
Calling mvebu_pwm_suspend() with mvpwm == NULL causes a NULL pointer
dereference when it tries to access mvpwm->blink_select.
Unable to handle kernel NULL pointer dereference at virtual address 00000020 when write
[00000020] *pgd=00000000
Internal error: Oops: 815 [#1] PREEMPT ARM
Modules linked in:
CPU: 0 UID: 0 PID: 406 Comm: sh Not tainted 6.12.74-rt12-yocto-standard-g4e96f98fb7db-dirty #353
Hardware name: Marvell Armada 370/XP (Device Tree)
PC is at regmap_mmio_read+0x38/0x54
LR is at regmap_mmio_read+0x38/0x54
pc : [<c05fd2ac>] lr : [<c05fd2ac>] psr: 200f0013
sp : f0c11d10 ip : 00000000 fp : c100d2f0
r10: c14fb854 r9 : 00000000 r8 : 00000000
r7 : c1799c00 r6 : 00000020 r5 : 00000020 r4 : c179c7c0
r3 : f0a231a0 r2 : 00000020 r1 : 00000020 r0 : 00000000
Flags: nzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none
Control: 10c5387d Table: 135ec059 DAC: 00000051
Call trace:
regmap_mmio_read from _regmap_bus_reg_read+0x78/0xac
_regmap_bus_reg_read from _regmap_read+0x60/0x154
_regmap_read from regmap_read+0x3c/0x60
regmap_read from mvebu_gpio_suspend+0xa4/0x14c
mvebu_gpio_suspend from dpm_run_callback+0x54/0x180
dpm_run_callback from device_suspend+0x124/0x630
device_suspend from dpm_suspend+0x124/0x270
dpm_suspend from dpm_suspend_start+0x64/0x6c
dpm_suspend_start from suspend_devices_and_enter+0x140/0x8e8
suspend_devices_and_enter from pm_suspend+0x2fc/0x308
pm_suspend from state_store+0x6c/0xc8
state_store from kernfs_fop_write_iter+0x10c/0x1f8
kernfs_fop_write_iter from vfs_write+0x270/0x468
vfs_write from ksys_write+0x70/0xf0
ksys_write from ret_fast_syscall+0x0/0x54
Add a NULL check for mvchip->mvpwm before calling the PWM
suspend/resume functions.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-06-25