CVE-2026-93106

In the Linux kernel, the following vulnerability has been resolved: crash_dump: release keyring reference at the correct time restore_dm_crypt_keys_to_thread_keyring() gets a reference to the user keyring before restoring the saved dm-crypt keys. The same keyring reference is then passed to add_key_to_keyring() for each saved key, but add_key_to_keyring() drops that reference on every call. This is only balanced when exactly one key is restored. With multiple keys, the keyring reference is dropped too many times and may trigger a refcount underflow or use-after-free. When more than five keys are restored, a refcount underflow/use-after-free warning can be triggered. The early error paths after lookup_user_key() also return without dropping the keyring reference. Keep ownership of the keyring reference in restore_dm_crypt_keys_to_thread_keyring(), drop it once on all exit paths, and make add_key_to_keyring() only use the reference without consuming it.

CVSS

No CVSS.

References

Link	Resource
https://git.kernel.org/stable/c/ada2e5a44e99113e08ad9b7b71396c6c572204da
https://git.kernel.org/stable/c/b0f7343a002f9c8b8378011f60482c76f3216dfd
https://git.kernel.org/stable/c/ed566979f99c5516cad45a76ae25e2a4928ffb67

Configurations

No configuration.

History

17 Sep 2026, 17:18

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-17 17:18

Updated : 2026-09-17 17:18

NVD link : CVE-2026-93106

Mitre link : CVE-2026-93106

CVE.ORG link : CVE-2026-93106

JSON object : View

Products Affected

No product.

CWE

No CWE.

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