CVE-2021-33034
HIGHCVSS 7.8/10EPSS 0.83%
Last modified
CVE-2021-33034 is a high-severity vulnerability rated 7.8/10 on the CVSS scale. 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.. EPSS estimates a 0.83% chance of exploitation in the next 30 days.
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/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Linux | Linux Kernel | < 5.12.4 |
| Fedoraproject | Fedora | 34 |
| Debian | Debian Linux | 9.0 |
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://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://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
- Last Modified
- Status
- Modified
Frequently Asked Questions
What is CVE-2021-33034?
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.
How severe is CVE-2021-33034?
CVE-2021-33034 has a CVSS score of 7.8/10 (HIGH severity). The EPSS model estimates a 0.83% probability of exploitation in the next 30 days.
How do I fix CVE-2021-33034?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.
Are you affected by CVE-2021-33034?
Run a free Strix scan to check your systems for this vulnerability.
Scan your code nowSource: NVD / NIST