CVE-2021-33034
Vulnerability Summary
Timeline
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.
CVSS Metrics
- v3.1•HIGH•Score: 7.8CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- v2.0•MEDIUM•Score: 4.6AV:L/AC:L/Au:N/C:P/I:P/A:P
EPSS Trends
Current EPSS score: 0.82%• Percentile: 56%
Techniques & Countermeasures
- CWE-416•Use After Free
The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.
Affected Systems
- debian•linux
< 5.10.38-1 | < 5.10.38-1 | < 5.10.38-1 | < 5.10.38-1
- ubuntu•linux
all | < 4.4.0-219.252 | < 4.15.0-151.157 | < 5.4.0-77.86
- ubuntu•linux-aws
< 4.4.0-1099.104 | < 4.4.0-1135.149 | < 4.15.0-1109.116 | < 5.4.0-1051.53
- ubuntu•linux-aws-5.0
all
- ubuntu•linux-aws-5.3
all
- ubuntu•linux-aws-5.4
< 5.4.0-1051.53~18.04.1
- ubuntu•linux-aws-5.8
< 5.8.0-1041.43~20.04.1
- ubuntu•linux-aws-fips
< 4.15.0-2051.53 | all | < 5.4.0-1069.73+fips2
- ubuntu•linux-aws-hwe
< 4.15.0-1109.116~16.04.1
- ubuntu•linux-azure
< 4.15.0-1121.134~14.04.1 | < 4.15.0-1121.134~16.04.1 | all | < 5.4.0-1051.53
- ubuntu•linux-azure-4.15
< 4.15.0-1121.134
- ubuntu•linux-azure-5.3
all
- ubuntu•linux-azure-5.4
< 5.4.0-1051.53~18.04.1
- ubuntu•linux-azure-5.8
< 5.8.0-1039.42~20.04.1
- ubuntu•linux-azure-edge
all
- ubuntu•linux-azure-fde-5.15
< 5.15.0-1114.123~20.04.1
- ubuntu•linux-azure-fips
< 4.15.0-2033.37 | all | < 5.4.0-1073.76+fips1
- ubuntu•linux-bluefield
all | < 5.4.0-1013.16
- ubuntu•linux-dell300x
< 4.15.0-1027.32
- ubuntu•linux-fips
< 4.4.0-1069.75 | all | < 4.15.0-1066.75 | < 5.4.0-1028.32
- ubuntu•linux-gcp
< 4.15.0-1106.120~16.04.1 | all | < 5.4.0-1046.49
- ubuntu•linux-gcp-4.15
< 4.15.0-1106.120
- ubuntu•linux-gcp-5.3
all
- ubuntu•linux-gcp-5.4
< 5.4.0-1046.49~18.04.1
- ubuntu•linux-gcp-5.8
< 5.8.0-1038.40~20.04.1
- ubuntu•linux-gcp-edge
all
- ubuntu•linux-gcp-fips
< 4.15.0-2016.18 | all | < 5.4.0-1067.71~20.04.1
- ubuntu•linux-gke
< 5.4.0-1046.48
- ubuntu•linux-gke-4.15
all
- ubuntu•linux-gke-5.4
< 5.4.0-1046.48~18.04.1
- ubuntu•linux-gkeop
< 5.4.0-1018.19
- ubuntu•linux-gkeop-5.4
< 5.4.0-1018.19~18.04.1
- ubuntu•linux-hwe
< 4.15.0-151.157~16.04.1 | all
- ubuntu•linux-hwe-5.4
< 5.4.0-77.86~18.04.1
- ubuntu•linux-hwe-5.8
< 5.8.0-63.71~20.04.1
- ubuntu•linux-hwe-edge
all | all
- ubuntu•linux-intel-iot-realtime
all
- ubuntu•linux-kvm
< 4.4.0-1100.109 | < 4.15.0-1097.99 | < 5.4.0-1041.42
- ubuntu•linux-lts-xenial
< 4.4.0-219.252~14.04.1
- ubuntu•linux-oem
all
- ubuntu•linux-oem-5.10
< 5.10.0-1032.33
- ubuntu•linux-oem-5.6
all
- ubuntu•linux-oracle
< 4.15.0-1078.86~16.04.1 | < 4.15.0-1078.86 | < 5.4.0-1048.52
- ubuntu•linux-oracle-5.0
all
- ubuntu•linux-oracle-5.3
all
- ubuntu•linux-oracle-5.4
< 5.4.0-1048.52~18.04.1
- ubuntu•linux-oracle-5.8
< 5.8.0-1037.38~20.04.1
- ubuntu•linux-raspi
< 5.4.0-1038.41
- ubuntu•linux-raspi-5.4
< 5.4.0-1038.41~18.04.1
- ubuntu•linux-raspi-realtime
all
Showing first 50 affected entries in server-rendered view.
References (28)
- https://syzkaller.appspot.com/bug?id=2e1943a94647f7732dd6fc60368642d6e8dc91b1
- https://sites.google.com/view/syzscope/kasan-use-after-free-read-in-hci_send_acl
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=5c4c8c9544099bb9043a10a5318130a943e32fc3
- https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.12.4
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/GI7Z7UBWBGD3ABNIL2DC7RQDCGA4UVQW/
- https://lists.debian.org/debian-lts-announce/2021/06/msg00020.html
- https://lists.debian.org/debian-lts-announce/2021/06/msg00019.html
- https://access.redhat.com/errata/RHSA-2021:2563
- https://access.redhat.com/security/updates/classification/#important
- https://bugzilla.redhat.com/show_bug.cgi?id=1961305
- https://security.access.redhat.com/data/csaf/v2/advisories/2021/rhsa-2021_2563.json
- https://access.redhat.com/security/cve/CVE-2021-33034
- https://www.cve.org/CVERecord?id=CVE-2021-33034
- https://nvd.nist.gov/vuln/detail/CVE-2021-33034
- https://access.redhat.com/errata/RHSA-2021:2668
- https://security.access.redhat.com/data/csaf/v2/advisories/2021/rhsa-2021_2668.json
- https://ubuntu.com/security/CVE-2021-33034
- https://git.kernel.org/linus/5c4c8c9544099bb9043a10a5318130a943e32fc3
- https://ubuntu.com/security/notices/USN-4997-1
- https://ubuntu.com/security/notices/USN-5000-1
- https://ubuntu.com/security/notices/USN-5001-1
- https://ubuntu.com/security/notices/USN-5018-1
- https://ubuntu.com/security/notices/USN-5016-1
- https://ubuntu.com/security/notices/USN-5000-2
- https://ubuntu.com/security/notices/USN-4997-2
- https://ubuntu.com/security/notices/USN-5299-1
- https://ubuntu.com/security/notices/USN-5343-1
- https://security-tracker.debian.org/tracker/CVE-2021-33034