# CVE-2021-34981: linux: Linux Kernel Bluetooth CMTP Module Double Free Privilege Escalation Vulnerability

CVE-2021-34981 is fixed in linux on 1 platform, first by DEBIAN-CVE-2021-34981, released May 7, 2024. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2021-34981
- Priority: Routine
- CVSS: 6.7 (medium)
- EPSS: 0.0020
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: May 7, 2024

## Description

Linux Kernel Bluetooth CMTP Module Double Free Privilege Escalation Vulnerability. This vulnerability allows local attackers to escalate privileges on affected installations of Linux Kernel. An attacker must first obtain the ability to execute high-privileged code on the target system in order to exploit this vulnerability.  The specific flaw exists within the CMTP module. The issue results from the lack of validating the existence of an object prior to performing further free operations on the object. An attacker can leverage this vulnerability to escalate privileges and execute code in the context of the kernel. Was ZDI-CAN-11977.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | linux Debian 12.15 (bookworm) | 5.10.46-1 | [DEBIAN-CVE-2021-34981](https://patchblox.com/security/data/fix/linux/debian-cve-2021-34981.md) | May 7, 2024 |
| Linux | linux Debian 13.5 (trixie) | 5.10.46-1 | [DEBIAN-CVE-2021-34981](https://patchblox.com/security/data/fix/linux/debian-cve-2021-34981.md) | May 7, 2024 |
| Linux | linux Debian 14 | 5.10.46-1 | [DEBIAN-CVE-2021-34981](https://patchblox.com/security/data/fix/linux/debian-cve-2021-34981.md) | May 7, 2024 |

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