CVE-2021-33034

HighCVSS 7.8/10Last modified Aug 13, 2026

Description

In the Linux kernel before 5.12.4, net/bluetooth/hci_event.c has a use-after-free when destroying an hci_chan, aka CID-5c4c8c954409. This leads to writing an arbitrary value.

Metrics

CVSS 3.1 7.8/10CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Weakness enumeration

CWE-416

Affected software

Vendor	Product	Versions
n/a	n/a	n/a

References

https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.12.4Mailing List, Patch, Vendor Advisory
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=5c4c8c9544099bb9043a10a5318130a943e32fc3Mailing List, Patch, Vendor Advisory
https://lists.debian.org/debian-lts-announce/2021/06/msg00019.htmlThird Party Advisory
https://lists.debian.org/debian-lts-announce/2021/06/msg00020.htmlThird Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/GI7Z7UBWBGD3ABNIL2DC7RQDCGA4UVQW/Broken Link
https://sites.google.com/view/syzscope/kasan-use-after-free-read-in-hci_send_aclExploit, Third Party Advisory
https://syzkaller.appspot.com/bug?id=2e1943a94647f7732dd6fc60368642d6e8dc91b1Exploit, Mailing List, Third Party Advisory
https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.12.4Mailing List, Patch, Vendor Advisory
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=5c4c8c9544099bb9043a10a5318130a943e32fc3Mailing List, Patch, Vendor Advisory
https://lists.debian.org/debian-lts-announce/2021/06/msg00019.htmlThird Party Advisory
https://lists.debian.org/debian-lts-announce/2021/06/msg00020.htmlThird Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/GI7Z7UBWBGD3ABNIL2DC7RQDCGA4UVQW/Broken Link
https://sites.google.com/view/syzscope/kasan-use-after-free-read-in-hci_send_aclExploit, Third Party Advisory
https://syzkaller.appspot.com/bug?id=2e1943a94647f7732dd6fc60368642d6e8dc91b1Exploit, Mailing List, Third Party Advisory

Timeline

Published: May 14, 2021
Last modified: Aug 13, 2026
NVD status: Analyzed

Related CVEs from 2021

CVE-2021-330357.8Apache OpenOffice opens dBase/DBF documents and shows the contents as spreadsheets. DBF are database files with data organized in fields. Wh CVE-2021-330368.8In Apache Hadoop 2.2.0 to 2.10.1, 3.0.0-alpha1 to 3.1.4, 3.2.0 to 3.2.2, and 3.3.0 to 3.3.1, a user who can escalate to yarn user can possib CVE-2021-330375.3Apache Tomcat 10.0.0-M1 to 10.0.6, 9.0.0.M1 to 9.0.46 and 8.5.0 to 8.5.66 did not correctly parse the HTTP transfer-encoding request header CVE-2021-330387.5An issue was discovered in management/commands/hyperkitty_import.py in HyperKitty through 1.3.4. When importing a private mailing list's arc CVE-2021-33049.8Sagemcom F@ST 3686 v2 3.495 devices have a buffer overflow via a long sessionKey to the goform/login URI.CVE-2021-330406.1managers/views/iframe.js in FuturePress EPub.js before 0.3.89 allows XSS.CVE-2021-330416.1vmd through 1.34.0 allows 'div class="markdown-body"' XSS, as demonstrated by Electron remote code execution via require('child_process').ex CVE-2021-330449.8The identity authentication bypass vulnerability found in some Dahua products during the login process. Attackers can bypass device identity CVE-2021-330459.8The identity authentication bypass vulnerability found in some Dahua products during the login process. Attackers can bypass device identity CVE-2021-330469.8Some Dahua products have access control vulnerability in the password reset process. Attackers can exploit this vulnerability through specif CVE-2021-33057.8Beijing Feishu Technology Co., Ltd Feishu v3.40.3 was discovered to contain an untrusted search path vulnerability.CVE-2021-330547.5SOGo 2.x before 2.4.1 and 3.x through 5.x before 5.1.1 does not validate the signatures of any SAML assertions it receives. Any actor with n