How severe is CVE-2026-43215?

CVE-2026-43215 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-43215 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (23rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-43215?

CVE-2026-43215 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-43215?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2026-43215 have an EU (EUVD) identifier?

Yes. CVE-2026-43215 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-27777.

When was CVE-2026-43215 published?

CVE-2026-43215 was published on 2026-05-06 and last updated on 2026-06-17.

CVE-2026-43215

CVE-2026-43215 is a high-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 8.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-667.

Key facts

Severity: High (CVSS 3.x base score 8.8)
EPSS exploit prediction: 0% (23rd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-27777
Weakness: CWE-667
Affected product: Linux Linux Kernel
Published: 2026-05-06
Last modified: 2026-06-17

Description

In the Linux kernel, the following vulnerability has been resolved: cifs: Fix locking usage for tcon fields We used to use the cifs_tcp_ses_lock to protect a lot of objects that are not just the server, ses or tcon lists. We later introduced srv_lock, ses_lock and tc_lock to protect fields within the corresponding structs. This was done to provide a more granular protection and avoid unnecessary serialization. There were still a couple of uses of cifs_tcp_ses_lock to provide tcon fields. In this patch, I've replaced them with tc_lock.

Frequently asked questions

What is CVE-2026-43215?: In the Linux kernel, the following vulnerability has been resolved: cifs: Fix locking usage for tcon fields We used to use the cifs_tcp_ses_lock to protect a lot of objects that are not just the server, ses or tcon lists. We later introduced srv_lock, ses_lock and tc_lock to protect fields within the corresponding structs. This was done to provide a more granular protection and avoid unnecessary serialization. There were still a couple of uses of cifs_tcp_ses_lock to provide tcon fields. In this patch, I've replaced them with tc_lock.
How severe is CVE-2026-43215?: CVE-2026-43215 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-43215 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (23rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-43215?: CVE-2026-43215 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-43215?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-43215 have an EU (EUVD) identifier?: Yes. CVE-2026-43215 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-27777.
When was CVE-2026-43215 published?: CVE-2026-43215 was published on 2026-05-06 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*

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