How severe is CVE-2026-23106?

CVE-2026-23106 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2026-23106 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (1st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-23106?

CVE-2026-23106 primarily affects Linux Linux Kernel. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2026-23106?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-23106 have an EU (EUVD) identifier?

Yes. CVE-2026-23106 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-5435.

When was CVE-2026-23106 published?

CVE-2026-23106 was published on 2026-02-04 and last updated on 2026-06-17.

CVE-2026-23106

CVE-2026-23106 is a medium-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 5.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
EPSS exploit prediction: 0% (1st percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-5435
Affected product: Linux Linux Kernel
Published: 2026-02-04
Last modified: 2026-06-17

Description

In the Linux kernel, the following vulnerability has been resolved: timekeeping: Adjust the leap state for the correct auxiliary timekeeper When __do_ajdtimex() was introduced to handle adjtimex for any timekeeper, this reference to tk_core was not updated. When called on an auxiliary timekeeper, the core timekeeper would be updated incorrectly. This gets caught by the lock debugging diagnostics because the timekeepers sequence lock gets written to without holding its associated spinlock: WARNING: include/linux/seqlock.h:226 at __do_adjtimex+0x394/0x3b0, CPU#2: test/125 aux_clock_adj (kernel/time/timekeeping.c:2979) __do_sys_clock_adjtime (kernel/time/posix-timers.c:1161 kernel/time/posix-timers.c:1173) do_syscall_64 (arch/x86/entry/syscall_64.c:63 (discriminator 1) arch/x86/entry/syscall_64.c:94 (discriminator 1)) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:131) Update the correct auxiliary timekeeper.

Frequently asked questions

What is CVE-2026-23106?: In the Linux kernel, the following vulnerability has been resolved: timekeeping: Adjust the leap state for the correct auxiliary timekeeper When __do_ajdtimex() was introduced to handle adjtimex for any timekeeper, this reference to tk_core was not updated. When called on an auxiliary timekeeper, the core timekeeper would be updated incorrectly. This gets caught by the lock debugging diagnostics because the timekeepers sequence lock gets written to without holding its associated spinlock: WARNING: include/linux/seqlock.h:226 at __do_adjtimex+0x394/0x3b0, CPU#2: test/125 aux_clock_adj (kernel/time/timekeeping.c:2979) __do_sys_clock_adjtime (kernel/time/posix-timers.c:1161 kernel/time/posix-timers.c:1173) do_syscall_64 (arch/x86/entry/syscall_64.c:63 (discriminator 1) arch/x86/entry/syscall_64.c:94 (discriminator 1)) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:131) Update the correct auxiliary timekeeper.
How severe is CVE-2026-23106?: CVE-2026-23106 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2026-23106 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (1st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-23106?: CVE-2026-23106 primarily affects Linux Linux Kernel. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-23106?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-23106 have an EU (EUVD) identifier?: Yes. CVE-2026-23106 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-5435.
When was CVE-2026-23106 published?: CVE-2026-23106 was published on 2026-02-04 and last updated on 2026-06-17.

References

Affected products (7)

cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.19:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.19:rc2:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.19:rc3:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.19:rc4:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.19:rc5:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.19:rc6:*:*:*:*:*:*

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