CVE-2026-23340Signal Handler Race Condition in Linux

Severity
7.8HIGHNVD
EPSS
0.0%
top 97.71%
CISA KEV
Not in KEV
Exploit
No known exploits
Timeline
PublishedMar 25

Description

In the Linux kernel, the following vulnerability has been resolved: net: sched: avoid qdisc_reset_all_tx_gt() vs dequeue race for lockless qdiscs When shrinking the number of real tx queues, netif_set_real_num_tx_queues() calls qdisc_reset_all_tx_gt() to flush qdiscs for queues which will no longer be used. qdisc_reset_all_tx_gt() currently serializes qdisc_reset() with qdisc_lock(). However, for lockless qdiscs, the dequeue path is serialized by qdisc_run_begin/end() using qdisc->seqlock ins

CVSS vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitability: 1.8 | Impact: 5.9

Affected Packages5 packages

Linuxlinux/linux_kernel4.16.06.1.167+4
Debianlinux/linux_kernel< 6.19.8-1
CVEListV5linux/linux6b3ba9146fe64b9bebb6346c9dcfe3b4851de2d77594467c49bfc2f4644dee0415ac2290db11fa0d+6
debiandebian/linux< linux 6.19.8-1 (forky)

🔴Vulnerability Details

3
GHSA
GHSA-27rj-chmq-rh6r: In the Linux kernel, the following vulnerability has been resolved: net: sched: avoid qdisc_reset_all_tx_gt() vs dequeue race for lockless qdiscs Wh2026-03-25
OSV
CVE-2026-23340: In the Linux kernel, the following vulnerability has been resolved: net: sched: avoid qdisc_reset_all_tx_gt() vs dequeue race for lockless qdiscs When2026-03-25
OSV
net: sched: avoid qdisc_reset_all_tx_gt() vs dequeue race for lockless qdiscs2026-03-25

📋Vendor Advisories

3
Red Hat
kernel: net: sched: avoid qdisc_reset_all_tx_gt() vs dequeue race for lockless qdiscs2026-03-25
Microsoft
net: sched: avoid qdisc_reset_all_tx_gt() vs dequeue race for lockless qdiscs2026-03-10
Debian
CVE-2026-23340: linux - In the Linux kernel, the following vulnerability has been resolved: net: sched:...2026

🕵️Threat Intelligence

1
Wiz
CVE-2026-23340 Impact, Exploitability, and Mitigation Steps | Wiz
CVE-2026-23340 — Signal Handler Race Condition in Linux | cvebase