UBUNTU-CVE-2021-4197
An unprivileged write to the file handler flaw in the Linux kernel's control groups and namespaces subsystem was found in the way users have access to some less privileged process that are controlled by cgroups and have higher privileged parent process. It is actually both for cgroup2 and cgroup1 versions of control groups. A local user could use this flaw to crash the system or escalate their privileges on the system.
02 / AFFECTED SOFTWARE
Affected packages
50 explicit affected versions
6 explicit affected versions
12 explicit affected versions
6 explicit affected versions
20 explicit affected versions
85 explicit affected versions
46 explicit affected versions
65 explicit affected versions
38 explicit affected versions
9 explicit affected versions
98 explicit affected versions
5 explicit affected versions
4 explicit affected versions
23 explicit affected versions
75 explicit affected versions
1 explicit affected versions
1 explicit affected versions
21 explicit affected versions
8 explicit affected versions
5 explicit affected versions
7 explicit affected versions
12 explicit affected versions
12 explicit affected versions
1 explicit affected versions
7 explicit affected versions
12 explicit affected versions
50 explicit affected versions
11 explicit affected versions
58 explicit affected versions
12 explicit affected versions
49 explicit affected versions
40 explicit affected versions
10 explicit affected versions
141 explicit affected versions
33 explicit affected versions
74 explicit affected versions
62 explicit affected versions
1 explicit affected versions
1 explicit affected versions
26 explicit affected versions
5 explicit affected versions
1 explicit affected versions
29 explicit affected versions
13 explicit affected versions
79 explicit affected versions
1 explicit affected versions
51 explicit affected versions
33 explicit affected versions
10 explicit affected versions
64 explicit affected versions
11 explicit affected versions
12 explicit affected versions
87 explicit affected versions
7 explicit affected versions
49 explicit affected versions
2 explicit affected versions
82 explicit affected versions
46 explicit affected versions
1 explicit affected versions
17 explicit affected versions
28 explicit affected versions
41 explicit affected versions
5 explicit affected versions
1 explicit affected versions
1 explicit affected versions
45 explicit affected versions
5 explicit affected versions
40 explicit affected versions
1 explicit affected versions
38 explicit affected versions
13 explicit affected versions
6 explicit affected versions
41 explicit affected versions
10 explicit affected versions
5 explicit affected versions
36 explicit affected versions
44 explicit affected versions
16 explicit affected versions
13 explicit affected versions
33 explicit affected versions
38 explicit affected versions
9 explicit affected versions
118 explicit affected versions
39 explicit affected versions
53 explicit affected versions
17 explicit affected versions
95 explicit affected versions
72 explicit affected versions
4 explicit affected versions
28 explicit affected versions
63 explicit affected versions
39 explicit affected versions
43 explicit affected versions
6 explicit affected versions
96 explicit affected versions
113 explicit affected versions
40 explicit affected versions
4 explicit affected versions
28 explicit affected versions
1 explicit affected versions
19 explicit affected versions
03 / CONNECTIONS
Connected vulnerabilities
04 / EVIDENCE
Source records
An unprivileged write to the file handler flaw in the Linux kernel's control groups and namespaces subsystem was found in the way users have access to some less privileged process that are controlled by cgroups and have higher privileged parent process. It is actually both for cgroup2 and cgroup1 versions of control groups. A local user could use this flaw to crash the system or escalate their privileges on the system.
05 / REFERENCES
Further evidence
- https://bugzilla.redhat.com/show_bug.cgi?id=2035652
- https://lore.kernel.org/lkml/[email protected]/T/
- https://ubuntu.com/security/CVE-2021-4197
- https://ubuntu.com/security/notices/USN-5278-1
- https://ubuntu.com/security/notices/USN-5337-1
- https://ubuntu.com/security/notices/USN-5368-1
- https://ubuntu.com/security/notices/USN-5467-1
- https://ubuntu.com/security/notices/USN-5500-1
- https://ubuntu.com/security/notices/USN-5505-1
- https://ubuntu.com/security/notices/USN-5513-1
- https://ubuntu.com/security/notices/USN-5515-1
- https://ubuntu.com/security/notices/USN-5541-1
- https://www.cve.org/CVERecord?id=CVE-2021-4197