What’s Vulnerable › Vulnerabilities

CVE-2021-3752

• Severity: high (CVSS 7.1 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 1.7% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2022-02-16 · updated 2026-06-17
• Weakness: CWE-416

Description

A use-after-free flaw was found in the Linux kernel’s Bluetooth subsystem in the way user calls connect to the socket and disconnect simultaneously due to a race condition. This flaw allows a user to crash the system or escalate their privileges. The highest threat from this vulnerability is to confidentiality, integrity, as well as system availability.

Affected products

• Debian Linux: 9.0, 10.0
• Fedoraproject Fedora: 34
• Linux kernel: from 2.6.12 before 4.4.293; from 4.5 before 4.9.291; from 4.10 before 4.14.256; from 4.15 before 4.19.218; from 4.20 before 5.4.160; from 5.5 before 5.10.80 — fixed in 4.14.256, 4.19.218, 4.4.293, 4.9.291, 5.10.80, 5.14.19
• NetApp H300E Firmware: all versions
• NetApp H300S Firmware: all versions
• NetApp H410C Firmware: all versions
• NetApp H410S Firmware: all versions
• NetApp H500E Firmware: all versions
• NetApp H500S Firmware: all versions
• NetApp H700E Firmware: all versions
• NetApp H700S Firmware: all versions
• Oracle Communications Cloud Native Core Binding Support Function: 22.1.3
• Oracle Communications Cloud Native Core Network Exposure Function: 22.1.1
• Oracle Communications Cloud Native Core Policy: 22.2.0
• 3scale: 2.0
• Red Hat Enterprise Linux: 7.0, 8.0
• RedHat Enterprise Linux For Real Time: 7
• RedHat Enterprise Linux For Real Time For Nfv: 7
• RedHat Virtualization Host: 4.0

How to fix

Upgrade to a fixed version: Linux kernel 4.14.256, 4.19.218, 4.4.293, 4.9.291. Check the vendor advisory for mitigations.

References

• https://bugzilla.redhat.com/show_bug.cgi?id=1999544
• https://lists.debian.org/debian-lts-announce/2022/03/msg00011.html
• https://lists.debian.org/debian-lts-announce/2022/03/msg00012.html
• https://lore.kernel.org/lkml/20211115165435.133245729%40linuxfoundation.org/
• https://security.netapp.com/advisory/ntap-20220318-0009/
• https://www.debian.org/security/2022/dsa-5096
• https://www.openwall.com/lists/oss-security/2021/09/15/4
• https://www.oracle.com/security-alerts/cpujul2022.html
• https://bugzilla.redhat.com/show_bug.cgi?id=1999544
• https://lists.debian.org/debian-lts-announce/2022/03/msg00011.html
• https://lists.debian.org/debian-lts-announce/2022/03/msg00012.html
• https://lore.kernel.org/lkml/20211115165435.133245729%40linuxfoundation.org/

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