CVE-2026-53296

Kernel memory corruption via uncleared probe channels

Published Jun 26, 2026 · Updated Jun 26, 2026

Use-after-free in the mailbox-test driver in affected Linux Kernel branches allows local users to corrupt kernel memory during probe failure. The mbox_test_probe function returns after receive-buffer allocation or debugfs setup errors without freeing acquired transmit and receive channels, while devm removes their client structure. Exploitation requires local low-privileged access and a probe failure after channel acquisition, leaving stale channels that expose freed client state to kernel access and crashes.

CVSS severity7.8
High
EPSS probability0.13%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Use-after-free in the mailbox-test driver in affected Linux Kernel branches allows local users to corrupt kernel memory during probe failure. The mbox_test_probe function returns after receive-buffer allocation or debugfs setup errors without freeing acquired transmit and receive channels, while devm removes their client structure. Exploitation requires local low-privileged access and a probe failure after channel acquisition, leaving stale channels that expose freed client state to kernel access and crashes.

The record

CVE
CVE-2026-53296
Published
Jun 26, 2026
Updated
Jun 26, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
CWE-416, T1068
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Jun 26, 2026CVE publishedPublication date reported by the CVE source.
  2. Jun 26, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=4.4
  2. Affected versionversion=8ea4484d0c2bb4e2152261943fa1a3522654b1c7 <02beb178e2e159daeb8f992d7abb16a37da31664
  3. Affected versionversion=8ea4484d0c2bb4e2152261943fa1a3522654b1c7 <0ad8c4a03a358de7811ba1ab8cbd1fe76ad0ff6b
  4. Affected versionversion=8ea4484d0c2bb4e2152261943fa1a3522654b1c7 <15c4cc3850cfe1b973eb7b63c02314b267f06a64
  5. Affected versionversion=8ea4484d0c2bb4e2152261943fa1a3522654b1c7 <187069ccc3474516af32350e20d7e449160fa6de
  6. Affected versionversion=8ea4484d0c2bb4e2152261943fa1a3522654b1c7 <6c6ce2ccb4fcf1617fec83f91b21aa0265f30701
  7. Affected versionversion=8ea4484d0c2bb4e2152261943fa1a3522654b1c7 <742001919653e7313b4e91780c5d108be1692365
  8. Affected versionversion=8ea4484d0c2bb4e2152261943fa1a3522654b1c7 <81c9e7e4030e71391ab479c4c6e17b64802577aa
  9. Affected versionversion=8ea4484d0c2bb4e2152261943fa1a3522654b1c7 <c02053a9055d5fdfd32432287cca8958db1d5bc5

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=4.4; version=8ea4484d0c2bb4e2152261943fa1a3522654b1c7 <02beb178e2e159daeb8f992d7abb16a37da31664; version=8ea4484d0c2bb4e2152261943fa1a3522654b1c7 <0ad8c4a03a358de7811ba1ab8cbd1fe76ad0ff6b; version=8ea4484d0c2bb4e2152261943fa1a3522654b1c7 <15c4cc3850cfe1b973eb7b63c02314b267f06a64; version=8ea4484d0c2bb4e2152261943fa1a3522654b1c7 <187069ccc3474516af32350e20d7e449160fa6de; version=8ea4484d0c2bb4e2152261943fa1a3522654b1c7 <6c6ce2ccb4fcf1617fec83f91b21aa0265f30701; version=8ea4484d0c2bb4e2152261943fa1a3522654b1c7 <742001919653e7313b4e91780c5d108be1692365; version=8ea4484d0c2bb4e2152261943fa1a3522654b1c7 <81c9e7e4030e71391ab479c4c6e17b64802577aa; version=8ea4484d0c2bb4e2152261943fa1a3522654b1c7 <c02053a9055d5fdfd32432287cca8958db1d5bc5

Published CVSS scores

7.8NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-416Use After Free
T1068Exploitation for Privilege Escalation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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