CVE WatchAug 4, 2026

CVE-2024-27435

In the Linux kernel, the following vulnerability has been resolved: nvme: fix reconnection fail due to reserved tag allocation We found a

CVSS

7.5

High

EPSS

0.2%

KEV

—

Exploit Today

0-100

Published: May 17, 2024 · Last modified: Aug 4, 2026 · CWE-667

EPSS · 30d

0.2%EPSS · 30 days0.2%

2026-07-062026-08-03

Technical description

In the Linux kernel, the following vulnerability has been resolved: nvme: fix reconnection fail due to reserved tag allocation We found a issue on production environment while using NVMe over RDMA, admin_q reconnect failed forever while remote target and network is ok. After dig into it, we found it may caused by a ABBA deadlock due to tag allocation. In my case, the tag was hold by a keep alive request waiting inside admin_q, as we quiesced admin_q while reset ctrl, so the request maked as idle and will not process before reset success. As fabric_q shares tagset with admin_q, while reconnect remote target, we need a tag for connect command, but the only one reserved tag was held by keep alive command which waiting inside admin_q. As a result, we failed to reconnect admin_q forever. In order to fix this issue, I think we should keep two reserved tags for admin queue.

Official references

Related CVEs

CVECVSSEPSSKEVRExploitTitleMod.

CVE-2026-624268.8 HIG

13.8%

——4[This CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] To manage the system, sysctl and platform operations are used by the control domain or a possible Xenstore domain. Some of these operations may not be executed in parallel, so a system-wide lock each is used. The way those locks are acquired is, however, not providing any fairness. Furthermore, with XSM/Flask in use, the lock acquire will, for some operations, occur ahead of any permission checking. The sysctl issue is CVE-2026-62426. The platform-op issue is CVE-2026-62427.7d CVE-2026-533588.8 HIG

9.5%

——3In the Linux kernel, the following vulnerability has been resolved: Bluetooth: L2CAP: use chan timer to close channels in cleanup_listen() l2cap_chan_close() removes the channel from conn->chan_l, which must be done under conn->lock. cleanup_listen() runs under the parent sk_lock, so acquiring conn->lock would invert the established conn->lock -> chan->lock -> sk_lock order. Instead of calling l2cap_chan_close() directly, schedule l2cap_chan_timeout with delay 0 to close the channel asynchronously. The timeout handler already acquires conn->lock and chan->lock in the correct order. The timer is only armed when chan->conn is still set: if it is already NULL, l2cap_conn_del() has already processed this channel (l2cap_chan_del + l2cap_sock_teardown_cb + l2cap_sock_close_cb), so there is nothing left to do. If l2cap_conn_del() races in after the timer is armed, __clear_chan_timer() inside l2cap_chan_del() cancels it; if the timer has already fired, the handler returns harmlessly because chan->conn was cleared.13d CVE-2026-533265.5 MED

0.8%

——0In the Linux kernel, the following vulnerability has been resolved: debugobjects: Don't call fill_pool() in early boot hardirq context When booting a debug PREEMPT_RT kernel on an ARM64 system, a "inconsistent {HARDIRQ-ON-W} -> {IN-HARDIRQ-W} usage" lockdep warning message was reported to the console. During early boot, interrupts are enabled before the scheduler is enabled. In this window (before SYSTEM_SCHEDULING is set) interrupts can fire and in the hard interrupt context handler attempt to fill the pool This can lead to a deadlock when the interrupt occurred when the interrupt hits a region which holds a lock that is required to be taken in the allocation path. Add a new can_fill_pool() helper and reorder the exception rule and forbid this scenario by excluding allocations from hard interrupt context.12d CVE-2026-106475.3 MED

10.9%

——3The USB CDC-NCM device class (subsys/usb/device_next/class/usbd_cdc_ncm.c) ignores the return value of usbd_ep_enqueue() in its ethernet transmit callback cdc_ncm_send(). When the enqueue fails, the function still calls k_sem_take(&data->sync_sem, K_FOREVER), blocking on a completion semaphore that is only ever signaled from the bulk-IN transfer-completion callback. Because nothing was enqueued, that callback never fires and the calling thread — a shared network traffic-class TX thread — deadlocks permanently while holding the interface TX lock, halting transmission until reboot (and leaking the transmit buffer). The enqueue fails under conditions controlled by the attached USB host: usbd_ep_enqueue() returns -EPERM whenever the bus is suspended (a standard, persistent host operation), and the underlying udc_ep_enqueue() returns -EPERM/-ENODEV on disconnect, bus reset, or endpoint disable. The cdc_ncm_send() guard only checks the DATA_IFACE_ENABLED and IFACE_UP flags, not the suspended state, so a packet transmitted while the host holds the bus suspended reaches the failing enqueue and deadlocks the TX path. The realistic trigger is a bus suspend that occurs while the exported network interface is active and has traffic to send — host sleep, USB selective/auto-suspend, or hub power management — after which any device-originated packet deadlocks the path, recoverable only by reboot. The impact is a persistent loss of the virtual network connection between the host's NCM interface and the Zephyr device; because the deadlocked thread is a shared traffic-class TX thread, egress on other network interfaces can stall as well. There is no memory corruption or information disclosure. The defect was introduced with the CDC-NCM driver and shipped in releases through v4.4.0; it is fixed by checking the usbd_ep_enqueue() return value and freeing the buffer before the blocking wait.21d CVE-2026-533235.5 MED

0.6%

——0In the Linux kernel, the following vulnerability has been resolved: net: dsa: remove redundant netdev_lock_ops() from conduit ethtool ops DSA replaces the conduit (master) device's ethtool_ops with its own wrappers that aggregate stats from both the conduit and DSA switch ports. Taking the lock again inside the DSA wrappers causes a deadlock. Stumbled upon this when booting qemu with fbnic and CONFIG_NET_DSA_LOOP=y (which looks like some kind of testing device that auto-populates the ports of eth0). `ethtool -i` is enough to deadlock. This means we have basically zero coverage for DSA stuff with real ops locked devs. Remove the redundant netdev_lock_ops()/netdev_unlock_ops() calls from the DSA conduit ethtool wrappers.29d CVE-2026-533045.5 MED

1.1%

——0In the Linux kernel, the following vulnerability has been resolved: scsi: sg: Resolve soft lockup issue when opening /dev/sgX The parameter def_reserved_size defines the default buffer size reserved for each Sg_fd and should be restricted to a range between 0 and 1,048,576 (see https://tldp.org/HOWTO/SCSI-Generic-HOWTO/proc.html). Although the function sg_proc_write_dressz enforces this limit, it is possible to bypass it by directly modifying the module parameter as shown below, which then causes a soft lockup: echo -1 > /sys/module/sg/parameters/def_reserved_size exec 4<> /dev/sg0 watchdog: BUG: soft lockup - CPU#5 stuck for 26 seconds! [bash:537] Modules loaded: CPU: 5 UID: 0 PID: 537 Command: bash, kernel version 6.19.0-rc3+ #134, PREEMPT disabled Hardware: QEMU Standard PC (i440FX + PIIX, 1996), BIOS version 1.16.1-2.fc37 dated 04/01/2014 ... Call Trace: sg_build_reserve+0x5c/0xa0 sg_add_sfp+0x168/0x270 sg_open+0x16e/0x340 chrdev_open+0xbe/0x230 do_dentry_open+0x175/0x480 vfs_open+0x34/0xf0 do_open+0x265/0x3d0 path_openat+0x110/0x290 do_filp_open+0xc3/0x170 do_sys_openat2+0x71/0xe0 __x64_sys_openat+0x6d/0xa0 do_syscall_64+0x62/0x310 entry_SYSCALL_64_after_hwframe+0x76/0x7e The fix is to use module_param_cb to validate and reject invalid values assigned to def_reserved_size.29d