#VU63660 Double Free in Linux kernel - CVE-2021-3564

Vulnerability identifier: #VU63660

Vulnerability risk: Low

CVSSv4.0: 1.7 [CVSS:4.0/AV:P/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-3564

CWE-ID: CWE-415

Exploitation vector: Local

Exploit availability: No

Vulnerable software:
Linux kernel
Operating systems & Components / Operating system

Vendor: Linux Foundation

Description

The vulnerability allows a local attacker to perform a denial of service attack.

The vulnerability exists due to bluetooth subsystem in the Linux kernel does not properly handle HCI device detach events. An attacker with physical access to the system can trigger double free error and perform a denial of service attack.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Linux kernel: All versions

---

External links
https://bugzilla.redhat.com/show_bug.cgi?id=1964139
https://www.openwall.com/lists/oss-security/2021/06/01/2
https://www.openwall.com/lists/oss-security/2021/05/25/1
https://www.openwall.com/lists/oss-security/2021/05/25/1
https://lists.debian.org/debian-lts-announce/2021/06/msg00019.html
https://lists.debian.org/debian-lts-announce/2021/06/msg00020.html

---

Q & A

Can this vulnerability be exploited remotely?

No. The attacker should have physical access to the system in order to successfully exploit this vulnerability.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.