Is there a public exploit for CVE-2026-90587?

No public exploit for CVE-2026-90587 was found in Exploit-DB, Metasploit, Nuclei templates or public proof-of-concept repositories. That is an absence of evidence rather than proof that none exists.

How severe is CVE-2026-90587?

CVE-2026-90587 scores CVSS 4.6 (v3.1), rated medium.

What does CVE-2026-90587 affect?

CVE-2026-90587 affects zephyrproject Zephyr.

4.6 Medium

usbhdeviceinit() in subsys/usb/host/usbhdevice.c rejects a device whose device descriptor advertises bNumConfigurations == 0, but it only…

CVE-2026-90587

usbhdeviceinit() in subsys/usb/host/usbhdevice.c rejects a device whose device descriptor advertises bNumConfigurations == 0, but it only logs the error and jumps to the cleanup label without setting the return code. At that point the local err is still 0 from the preceding successful descriptor read, so the function returns success while having skipped usbhdevicesetconfiguration() — the only place udev->cfgdesc is allocated. The device structure is zero-initialised by usbhdevicealloc(), so udev->cfgdesc remains NULL. usbhdeviceconnect() treats the zero return as a successful enumeration and calls usbhclassprobedevice(), which starts its descriptor walk from udev->cfgdesc. usbhdescgetnextfunction() passes that NULL pointer to usbhdescisvalid(), whose only guard compares the caller-supplied size, so head->bLength is read through a NULL pointer. The condition is triggered entirely by the attached peripheral: attaching a USB device (or any USB gadget emulating one) that reports bNumConfigurations = 0 reaches the defect directly from the UHCEVTDEVCONNECTEDFS/HS event handler in subsys/usb/host/usbhcore.c, with no authentication and no user interaction beyond the physical attachment.…

Assessment

CVSS: 4.6 (v3.1)
Severity: Medium
Known exploited: Not listed in CISA KEV
Exploit availability: Nothing found in Exploit-DB, Metasploit, Nuclei or public PoC repositories
Published: 9 November 2026
Last updated: 9 November 2026
Affected: zephyrproject · Zephyr
Assigner: zephyr

CVSS vectorCVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

At the source

EUVD (ENISA)

References

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