CVE-2026-53294

Double-free via aliased mailbox channels

Published Jun 26, 2026 · Updated Jun 26, 2026

A double-free in the Linux Kernel mailbox-test driver allows attackers to release one aliased mailbox channel allocation twice. The cleanup paths free the TX channel and then free an RX channel that can identify the same object when the channels use different MMIO resources. Reachability requires the mailbox-test driver and that channel arrangement; the official record does not state the resulting security impact.

CVSS severity5.7
Medium
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

A double-free in the Linux Kernel mailbox-test driver allows attackers to release one aliased mailbox channel allocation twice. The cleanup paths free the TX channel and then free an RX channel that can identify the same object when the channels use different MMIO resources. Reachability requires the mailbox-test driver and that channel arrangement; the official record does not state the resulting security impact.

The record

CVE
CVE-2026-53294
Published
Jun 26, 2026
Updated
Jun 26, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
Unavailable
Attack vector
local
Privileges
admin

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

Compare your product and version with the public record. A matching version still requires validation against your environment.

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 <240c71a2aea36a1a4210f911a1c32ea88777e8e4
  3. Affected versionversion=8ea4484d0c2bb4e2152261943fa1a3522654b1c7 <3afca89fae501dbd7421e1777b5b8f033b1d98d0
  4. Affected versionversion=8ea4484d0c2bb4e2152261943fa1a3522654b1c7 <5c209299b0113e289e238fa5f2e8f00c59f76060
  5. Affected versionversion=8ea4484d0c2bb4e2152261943fa1a3522654b1c7 <5d4f3d0f64f1016cb78b400a70b67df91fac99b5
  6. Affected versionversion=8ea4484d0c2bb4e2152261943fa1a3522654b1c7 <82f6dcea46cf5de65c4ba7283f7c7b34de4a324d
  7. Affected versionversion=8ea4484d0c2bb4e2152261943fa1a3522654b1c7 <88ebadbf0deefdaccdab868b44ff70a0a257f473
  8. Affected versionversion=8ea4484d0c2bb4e2152261943fa1a3522654b1c7 <c494a11da45ad7ec9b0ff216c3e3ace351193bb6
  9. Affected versionversion=8ea4484d0c2bb4e2152261943fa1a3522654b1c7 <fc0089f82c3e36060c2c79156bc2018bfb16b56b

What conditions does exploitation require?

Attack vectorlocal
Required privilegesadmin

What is affected?

The Linux Kernel Organization · Linux Kernelversion=4.4; version=8ea4484d0c2bb4e2152261943fa1a3522654b1c7 <240c71a2aea36a1a4210f911a1c32ea88777e8e4; version=8ea4484d0c2bb4e2152261943fa1a3522654b1c7 <3afca89fae501dbd7421e1777b5b8f033b1d98d0; version=8ea4484d0c2bb4e2152261943fa1a3522654b1c7 <5c209299b0113e289e238fa5f2e8f00c59f76060; version=8ea4484d0c2bb4e2152261943fa1a3522654b1c7 <5d4f3d0f64f1016cb78b400a70b67df91fac99b5; version=8ea4484d0c2bb4e2152261943fa1a3522654b1c7 <82f6dcea46cf5de65c4ba7283f7c7b34de4a324d; version=8ea4484d0c2bb4e2152261943fa1a3522654b1c7 <88ebadbf0deefdaccdab868b44ff70a0a257f473; version=8ea4484d0c2bb4e2152261943fa1a3522654b1c7 <c494a11da45ad7ec9b0ff216c3e3ace351193bb6; version=8ea4484d0c2bb4e2152261943fa1a3522654b1c7 <fc0089f82c3e36060c2c79156bc2018bfb16b56b

Published CVSS scores

5.7SUSECVSS:4.0/AV:L/AC:L/AT:P/PR:H/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N
4.7SUSECVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:L/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
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

No sourced classifications are available.

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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