Linux Kernel up to 6.18.51/7.2.5 crash_dump restore_dm_crypt_keys_to_thread_keyring use after free

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.8$0-$5k0.39-

Summaryinfo

A vulnerability identified as very critical has been detected in Linux Kernel up to 6.18.51/7.2.5. Affected by this issue is the function restore_dm_crypt_keys_to_thread_keyring of the component crash_dump. Performing a manipulation results in use after free. This vulnerability is cataloged as CVE-2026-93106. The attack must be initiated from a local position. There is no exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as very critical, was found in Linux Kernel up to 6.18.51/7.2.5. This affects the function restore_dm_crypt_keys_to_thread_keyring of the component crash_dump. The manipulation with an unknown input leads to a use after free vulnerability. CWE is classifying the issue as CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

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.

It is possible to read the advisory at git.kernel.org. This vulnerability is uniquely identified as CVE-2026-93106 since 09/17/2026. The exploitability is told to be easy. Attacking locally is a requirement. Additional levels of successful authentication are needed for exploitation. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 09/17/2026).

Upgrading to version 6.18.52, 7.2.6 or 7.3-rc1 eliminates this vulnerability. Applying the patch b0f7343a002f9c8b8378011f60482c76f3216dfd/ed566979f99c5516cad45a76ae25e2a4928ffb67/ada2e5a44e99113e08ad9b7b71396c6c572204da is able to eliminate this problem. The best possible mitigation is suggested to be upgrading to the latest version.

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Productinfo

Type

Vendor

Name

Version

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Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.2
VulDB Meta Temp Score: 7.8

VulDB Base Score: 8.2
VulDB Temp Score: 7.8
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Use after free
CWE: CWE-416 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: No

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 6.18.52/7.2.6/7.3-rc1
Patch: b0f7343a002f9c8b8378011f60482c76f3216dfd/ed566979f99c5516cad45a76ae25e2a4928ffb67/ada2e5a44e99113e08ad9b7b71396c6c572204da

Timelineinfo

09/17/2026 Advisory disclosed
09/17/2026 +0 days CVE reserved
09/17/2026 +0 days VulDB entry created
09/17/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-93106 (🔒)
GCVE (CVE): GCVE-0-2026-93106
GCVE (VulDB): GCVE-100-407199

Entryinfo

Created: 09/17/2026 23:45
Changes: 09/17/2026 23:45 (59)
Complete: 🔍
Cache ID: 216::103

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