How severe is CVE-2026-43255?

CVE-2026-43255 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-2026-43255 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (3rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-43255?

CVE-2026-43255 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-43255?

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

Does CVE-2026-43255 have an EU (EUVD) identifier?

Yes. CVE-2026-43255 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-27814.

When was CVE-2026-43255 published?

CVE-2026-43255 was published on 2026-05-06 and last updated on 2026-06-17.

CVE-2026-43255

CVE-2026-43255 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% (3rd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-27814
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: wifi: libertas: fix WARNING in usb_tx_block The function usb_tx_block() submits cardp->tx_urb without ensuring that any previous transmission on this URB has completed. If a second call occurs while the URB is still active (e.g. during rapid firmware loading), usb_submit_urb() detects the active state and triggers a warning: 'URB submitted while active'. Fix this by enforcing serialization: call usb_kill_urb() before submitting the new request. This ensures the URB is idle and safe to reuse.

Frequently asked questions

What is CVE-2026-43255?: In the Linux kernel, the following vulnerability has been resolved: wifi: libertas: fix WARNING in usb_tx_block The function usb_tx_block() submits cardp->tx_urb without ensuring that any previous transmission on this URB has completed. If a second call occurs while the URB is still active (e.g. during rapid firmware loading), usb_submit_urb() detects the active state and triggers a warning: 'URB submitted while active'. Fix this by enforcing serialization: call usb_kill_urb() before submitting the new request. This ensures the URB is idle and safe to reuse.
How severe is CVE-2026-43255?: CVE-2026-43255 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-2026-43255 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (3rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-43255?: CVE-2026-43255 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-43255?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-43255 have an EU (EUVD) identifier?: Yes. CVE-2026-43255 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-27814.
When was CVE-2026-43255 published?: CVE-2026-43255 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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