CVE-2026-64376: In the Linux kernel, the following vulnerability has been resolved: firmware_loader: fix device reference leak in firmware_upload_register() firmware_upload_register() -> fw_cr
In the Linux kernel, the following vulnerability has been resolved:
firmware_loader: fix device reference leak in firmware_upload_register()
firmware_upload_register()
-> fw_create_instance()
-> device_initialize()
After fw_create_instance() succeeds, the lifetime of the embedded struct
device is expected to be managed through the device core reference
counting, since fw_create_instance() has already called
device_initialize().
In firmware_upload_register(), if alloc_lookup_fw_priv() fails after
fw_create_instance() succeeds, the code reaches free_fw_sysfs and frees
fw_sysfs directly instead of releasing the device reference with
put_device(). This may leave the reference count of the embedded struct
device unbalanced, resulting in a refcount leak.
The issue was identified by a static analysis tool I developed and
confirmed by manual review. Fix this by using put_device(fw_dev) in the
failure path and letting fw_dev_release() handle the final cleanup,
instead of freeing the instance directly from the error path.
Details
Original advisory: https://nvd.nist.gov/vuln/detail/CVE-2026-64376
Exploitation outlook
EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.
- Low exploitation riskCVE-2026-643760.17% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 7% of all scored CVEs.
Referenced CVEs
| CVE | CSIRTS overview | External |
|---|---|---|
| CVE-2026-64376 | coverage & exploitation status | NVD · CVE.org |
Same CVEs, other sources
How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.
Recent advisories for In the Linux
A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.
- unknownUbuntu Linux Kernel Multiple Vulnerabilitieshkcert · 2026-08-03
- unknownRedHat Linux Kernel Multiple Vulnerabilitieshkcert · 2026-08-03
- highUSN-8620-4: Linux kernel (Intel IoTG) vulnerabilitiesubuntu · 2026-07-31
- highCVE-2026-18358: A flaw was found in gnome-remote-desktop as shipped in Red Hat Enterprise Linux. When the daem…nvd · 2026-07-31
- medium[UPDATE] [medium] Linux Kernel: Multiple vulnerabilities allow denial of servicecert-bund · 2026-07-31
- medium[UPDATE] [medium] Linux Kernel: Multiple vulnerabilities allow Denial of Servicecert-bund · 2026-07-31
More from NVD Recent CVEs
- unknownCVE-2026-58063: In Bouncy Castle for Java before 1.85, BCFKS keystore load honours unbounded KDF cost from unt…2026-08-03
- unknownCVE-2026-58062: In Bouncy Castle for Java before 1.85, Stapled OCSP response accepted without binding to the c…2026-08-03
- unknownCVE-2026-58061: In Bouncy Castle for Java before 1.85, CCM-family modes write plaintext to caller buffer befor…2026-08-03
- unknownCVE-2026-58060: In Bouncy Castle for Java before 1.85, HSS public-key level count unbounded, enabling huge all…2026-08-03
- unknownCVE-2026-58059: In Bouncy Castle for Java before 1.85, Quadratic-time escaping when stringifying X.500 disting…2026-08-03