# CVE-2026-53296: mailbox: mailbox-test: free channels on probe error

CVE-2026-53296 is fixed in linux on 1 platform, first by DEBIAN-CVE-2026-53296, released June 27, 2026. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2026-53296
- Priority: High
- CVSS: 7.8 (Moderate)
- EPSS: 0.0018
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Jun 26, 2026
- Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-53296

## Description

In the Linux kernel, the following vulnerability has been resolved:  mailbox: mailbox-test: free channels on probe error  On probe error, free the previously obtained channels. This not only prevents a leak, but also UAF scenarios because the client structure will be removed nonetheless because it was allocated with devm.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | linux Debian 12.15 (bookworm) | 6.1.176-1 | [DEBIAN-CVE-2026-53296](https://patchblox.com/security/data/fix/linux/debian-cve-2026-53296.md) | Jun 27, 2026 |
| Linux | linux Debian 13.5 (trixie) | 6.12.94-1 | [DEBIAN-CVE-2026-53296](https://patchblox.com/security/data/fix/linux/debian-cve-2026-53296.md) | Jun 27, 2026 |
| Linux | linux Debian 14 | 7.0.10-1 | [DEBIAN-CVE-2026-53296](https://patchblox.com/security/data/fix/linux/debian-cve-2026-53296.md) | Jun 27, 2026 |

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Data as of 2026-11-08T00:53:09Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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