CVE-2026-53025
In the Linux kernel, the following vulnerability has been resolved: greybus: raw: fix use-after-free on cdev close This addresses a use-after-free bug when a raw bundle is disconnected but its chardev is still opened by an application. When the application releases the cdev, it causes the following panic when init on free is enabled (CONFIG_INIT_ON_FREE_DEFAULT_ON=y): refcount_t: underflow; use-after-free. WARNING: CPU: 0 PID: 139 at lib/refcount.c:28 refcount_warn_saturate+0xd0/0x130 ... Call Trace: <TASK> cdev_put+0x18/0x30 __fput+0x255/0x2a0 __x64_sys_close+0x3d/0x80 do_syscall_64+0xa4/0x290 entry_SYSCALL_64_after_hwframe+0x77/0x7f The cdev is contained in the "gb_raw" structure, which is freed in the disconnect operation. When the cdev is released at a later time, cdev_put gets an address that points to freed memory. To fix this use-after-free, convert the struct device from a pointer to being embedded, that makes the lifetime of the cdev and of this device the same. Then, use cdev_device_add, which guarantees that the device won't be released until all references to the cdev have been released. Finally, delegate the freeing of the structure to the device release function, instead of freeing immediately in the disconnect callback.
Affected versions
Linux kernel versions
4.9
and later are affected. Fixed in
7.0.10,
7.1
and their respective stable series.
References
2 totalFrequently asked questions
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What is CVE-2026-53025?
CVE-2026-53025 is a unscored severity Linux kernel vulnerability . It affects Linux kernel versions from 4.9 onward and has been patched in 7.0.10 and 7.1. CVE-2026-53025 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
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Is there a patch available for CVE-2026-53025?
Yes — CVE-2026-53025 has been patched. Fixed versions include 7.0.10 and 7.1. If you are running Linux kernel 4.9 or later up to the fix versions, apply the relevant patch for your kernel branch.
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Is CVE-2026-53025 actively exploited?
No — CVE-2026-53025 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.