CVE-2026-99222
keys: Protect the read method check against type removal
Published Nov 2, 2026
CVSS 3.1 · 4.7 Medium
EPSS < 1%
KEV · Not listed
Description
In the Linux kernel, the following vulnerability has been resolved:
keys: Protect the read method check against type removal
keyctl_read_key() checks key->type->read without holding key->sem.
A reference keeps the key alive, but does not pin the module containing
its type. A surviving RxRPC key can therefore be read while AF_RXRPC
is being unloaded:
KEYCTL_READ task Module unload and key GC
---------------- ------------------------
lookup_user_key()
permission / possession checks
load key->type
af_rxrpc_exit()
unregister_key_type()
GC: down_write(key->sem)
GC: retype to key_type_dead
GC: up_write(key->sem)
unregister_key_type() returns
free_module()
read saved type's read member
The final access can read freed module storage. The read invocation in
__keyctl_read_key() is already protected by key->sem, but the earlier
method check is outside that critical section.
Move the method check into __keyctl_read_key(), after key_validate() and
under its existing read hold on key->sem. The check and invocation then
use the same protected type for length queries and every read retry.
The GC cannot retype the key until the semaphore is released, and type
unregistration waits for that GC pass before the module can be freed.
Return -EOPNOTSUPP when validation succeeds and the type has no read
method. A temporary buffer may now be allocated before this result;
allocation and copying to userspace remain outside the semaphore.
keys: Protect the read method check against type removal
keyctl_read_key() checks key->type->read without holding key->sem.
A reference keeps the key alive, but does not pin the module containing
its type. A surviving RxRPC key can therefore be read while AF_RXRPC
is being unloaded:
KEYCTL_READ task Module unload and key GC
---------------- ------------------------
lookup_user_key()
permission / possession checks
load key->type
af_rxrpc_exit()
unregister_key_type()
GC: down_write(key->sem)
GC: retype to key_type_dead
GC: up_write(key->sem)
unregister_key_type() returns
free_module()
read saved type's read member
The final access can read freed module storage. The read invocation in
__keyctl_read_key() is already protected by key->sem, but the earlier
method check is outside that critical section.
Move the method check into __keyctl_read_key(), after key_validate() and
under its existing read hold on key->sem. The check and invocation then
use the same protected type for length queries and every read retry.
The GC cannot retype the key until the semaphore is released, and type
unregistration waits for that GC pass before the module can be freed.
Return -EOPNOTSUPP when validation succeeds and the type has no read
method. A temporary buffer may now be allocated before this result;
allocation and copying to userspace remain outside the semaphore.
Affected Products
-
CVE record
-
NVD configurations
No data
-
Red Hat packages
No data
-
OpenCVE enrichment
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | ||||||||||||||||||||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Linux | Linux | unaffected |
|
||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Linux | Linux | affected |
|
No data.
No data.
| Vendor | Product | Versions | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Linux | Linux |
|
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Linux | Linux |
|
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Linux | Linux Kernel |
|
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Linux | Linux Kernel |
|
Remediation
Tracking
Advisories
| Source | ID | Title |
|---|---|---|
 Debian DLA |
DLA-4904-1 | linux-6.12 security update |
Metrics
No CVSS v4.0
Attack Vector Local
Attack Complexity High
Privileges Required Low
Scope Unchanged
Confidentiality Impact None
Integrity Impact None
Availability Impact High
User Interaction None
No CVSS v3.0
No CVSS v2
This CVE is not in the KEV list.
Exploit prediction score: < 1% (0.182% probability within 30 days)
Key SSVC decision points have not yet been added.
References
History
Nov 4, 2026 12:15 PM
Weaknesses updated. Added references. Scoring metrics updated
View changes
| Type | Values Removed | Values Added |
|---|---|---|
| Weaknesses | CWE-825 | |
| References |
| |
| Metrics |
threat_severity
|
cvssV3_1
|
Nov 3, 2026 7:30 PM
Added references
View changes
| Type | Values Removed | Values Added |
|---|---|---|
| References |
|
Nov 2, 2026 6:30 PM
Weaknesses updated
View changes
| Type | Values Removed | Values Added |
|---|---|---|
| Weaknesses | CWE-416 |
Nov 2, 2026 6:00 PM
First appearance in the feed. Affected vendors updated
View changes
| Type | Values Removed | Values Added |
|---|---|---|
| First Time appeared |
Linux linux
|
|
| Vendors & Products |
Linux linux
|
Nov 2, 2026 4:15 PM
Description updated. Title updated. First appearance in the feed. Affected versions updated. Affected vendors updated. Added references
View changes
| Type | Values Removed | Values Added |
|---|---|---|
| Description | In the Linux kernel, the following vulnerability has been resolved: keys: Protect the read method check against type removal keyctl_read_key() checks key->type->read without holding key->sem. A reference keeps the key alive, but does not pin the module containing its type. A surviving RxRPC key can therefore be read while AF_RXRPC is being unloaded: KEYCTL_READ task Module unload and key GC ---------------- ------------------------ lookup_user_key() permission / possession checks load key->type af_rxrpc_exit() unregister_key_type() GC: down_write(key->sem) GC: retype to key_type_dead GC: up_write(key->sem) unregister_key_type() returns free_module() read saved type's read member The final access can read freed module storage. The read invocation in __keyctl_read_key() is already protected by key->sem, but the earlier method check is outside that critical section. Move the method check into __keyctl_read_key(), after key_validate() and under its existing read hold on key->sem. The check and invocation then use the same protected type for length queries and every read retry. The GC cannot retype the key until the semaphore is released, and type unregistration waits for that GC pass before the module can be freed. Return -EOPNOTSUPP when validation succeeds and the type has no read method. A temporary buffer may now be allocated before this result; allocation and copying to userspace remain outside the semaphore. | |
| Title | keys: Protect the read method check against type removal | |
| First Time appeared |
Linux
Linux linux Kernel |
|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
|
| References |
|
|
