UBUNTU-CVE-2026-23410
In the Linux kernel, the following vulnerability has been resolved: apparmor: fix race on rawdata dereference There is a race condition that leads to a use-after-free situation: because the rawdata inodes are not refcounted, an attacker can start open()ing one of the rawdata files, and at the same time remove the last reference to this rawdata (by removing the corresponding profile, for example), which frees its struct aa_loaddata; as a result, when seq_rawdata_open() is reached, i_private is a dangling pointer and freed memory is accessed. The rawdata inodes weren't refcounted to avoid a circular refcount and were supposed to be held by the profile rawdata reference. However during profile removal there is a window where the vfs and profile destruction race, resulting in the use after free. Fix this by moving to a double refcount scheme. Where the profile refcount on rawdata is used to break the circular dependency. Allowing for freeing of the rawdata once all inode references to the rawdata are put.
02 / AFFECTED SOFTWARE
Affected packages
11 explicit affected versions
47 explicit affected versions
110 explicit affected versions
80 explicit affected versions
50 explicit affected versions
6 explicit affected versions
34 explicit affected versions
1 explicit affected versions
1 explicit affected versions
96 explicit affected versions
82 explicit affected versions
45 explicit affected versions
33 explicit affected versions
23 explicit affected versions
51 explicit affected versions
10 explicit affected versions
13 explicit affected versions
12 explicit affected versions
111 explicit affected versions
11 explicit affected versions
5 explicit affected versions
12 explicit affected versions
2 explicit affected versions
134 explicit affected versions
7 explicit affected versions
12 explicit affected versions
1 explicit affected versions
9 explicit affected versions
5 explicit affected versions
67 explicit affected versions
126 explicit affected versions
83 explicit affected versions
148 explicit affected versions
10 explicit affected versions
26 explicit affected versions
32 explicit affected versions
1 explicit affected versions
59 explicit affected versions
28 explicit affected versions
40 explicit affected versions
11 explicit affected versions
2 explicit affected versions
13 explicit affected versions
39 explicit affected versions
134 explicit affected versions
73 explicit affected versions
16 explicit affected versions
81 explicit affected versions
43 explicit affected versions
3 explicit affected versions
126 explicit affected versions
88 explicit affected versions
1 explicit affected versions
7 explicit affected versions
2 explicit affected versions
8 explicit affected versions
51 explicit affected versions
9 explicit affected versions
87 explicit affected versions
18 explicit affected versions
35 explicit affected versions
12 explicit affected versions
66 explicit affected versions
70 explicit affected versions
2 explicit affected versions
27 explicit affected versions
57 explicit affected versions
115 explicit affected versions
1 explicit affected versions
1 explicit affected versions
92 explicit affected versions
36 explicit affected versions
8 explicit affected versions
47 explicit affected versions
5 explicit affected versions
8 explicit affected versions
1 explicit affected versions
10 explicit affected versions
7 explicit affected versions
39 explicit affected versions
13 explicit affected versions
104 explicit affected versions
13 explicit affected versions
66 explicit affected versions
7 explicit affected versions
8 explicit affected versions
89 explicit affected versions
10 explicit affected versions
12 explicit affected versions
9 explicit affected versions
30 explicit affected versions
103 explicit affected versions
75 explicit affected versions
50 explicit affected versions
44 explicit affected versions
16 explicit affected versions
3 explicit affected versions
13 explicit affected versions
26 explicit affected versions
45 explicit affected versions
37 explicit affected versions
44 explicit affected versions
14 explicit affected versions
38 explicit affected versions
9 explicit affected versions
10 explicit affected versions
11 explicit affected versions
32 explicit affected versions
15 explicit affected versions
7 explicit affected versions
83 explicit affected versions
8 explicit affected versions
7 explicit affected versions
137 explicit affected versions
117 explicit affected versions
4 explicit affected versions
73 explicit affected versions
1 explicit affected versions
1 explicit affected versions
1 explicit affected versions
1 explicit affected versions
81 explicit affected versions
107 explicit affected versions
72 explicit affected versions
71 explicit affected versions
13 explicit affected versions
43 explicit affected versions
71 explicit affected versions
8 explicit affected versions
113 explicit affected versions
162 explicit affected versions
10 explicit affected versions
8 explicit affected versions
38 explicit affected versions
83 explicit affected versions
14 explicit affected versions
4 explicit affected versions
78 explicit affected versions
7 explicit affected versions
11 explicit affected versions
1 explicit affected versions
64 explicit affected versions
117 explicit affected versions
12 explicit affected versions
32 explicit affected versions
71 explicit affected versions
12 explicit affected versions
19 explicit affected versions
10 explicit affected versions
6 explicit affected versions
90 explicit affected versions
24 explicit affected versions
75 explicit affected versions
75 explicit affected versions
85 explicit affected versions
79 explicit affected versions
70 explicit affected versions
10 explicit affected versions
30 explicit affected versions
26 explicit affected versions
82 explicit affected versions
7 explicit affected versions
77 explicit affected versions
34 explicit affected versions
13 explicit affected versions
80 explicit affected versions
37 explicit affected versions
35 explicit affected versions
42 explicit affected versions
40 explicit affected versions
18 explicit affected versions
35 explicit affected versions
113 explicit affected versions
64 explicit affected versions
39 explicit affected versions
115 explicit affected versions
13 explicit affected versions
4 explicit affected versions
23 explicit affected versions
45 explicit affected versions
118 explicit affected versions
1 explicit affected versions
1 explicit affected versions
21 explicit affected versions
9 explicit affected versions
16 explicit affected versions
10 explicit affected versions
13 explicit affected versions
70 explicit affected versions
41 explicit affected versions
8 explicit affected versions
7 explicit affected versions
12 explicit affected versions
11 explicit affected versions
7 explicit affected versions
12 explicit affected versions
14 explicit affected versions
10 explicit affected versions
1 explicit affected versions
7 explicit affected versions
9 explicit affected versions
99 explicit affected versions
12 explicit affected versions
2 explicit affected versions
101 explicit affected versions
12 explicit affected versions
34 explicit affected versions
36 explicit affected versions
16 explicit affected versions
10 explicit affected versions
23 explicit affected versions
27 explicit affected versions
10 explicit affected versions
37 explicit affected versions
10 explicit affected versions
2 explicit affected versions
13 explicit affected versions
33 explicit affected versions
3 explicit affected versions
10 explicit affected versions
11 explicit affected versions
58 explicit affected versions
1 explicit affected versions
26 explicit affected versions
5 explicit affected versions
13 explicit affected versions
29 explicit affected versions
1 explicit affected versions
29 explicit affected versions
105 explicit affected versions
13 explicit affected versions
12 explicit affected versions
87 explicit affected versions
34 explicit affected versions
03 / CONNECTIONS
Connected vulnerabilities
04 / EVIDENCE
Source records
In the Linux kernel, the following vulnerability has been resolved: apparmor: fix race on rawdata dereference There is a race condition that leads to a use-after-free situation: because the rawdata inodes are not refcounted, an attacker can start open()ing one of the rawdata files, and at the same time remove the last reference to this rawdata (by removing the corresponding profile, for example), which frees its struct aa_loaddata; as a result, when seq_rawdata_open() is reached, i_private is a dangling pointer and freed memory is accessed. The rawdata inodes weren't refcounted to avoid a circular refcount and were supposed to be held by the profile rawdata reference. However during profile removal there is a window where the vfs and profile destruction race, resulting in the use after free. Fix this by moving to a double refcount scheme. Where the profile refcount on rawdata is used to break the circular dependency. Allowing for freeing of the rawdata once all inode references to the rawdata are put.
05 / REFERENCES
Further evidence
- https://cdn2.qualys.com/advisory/2026/03/10/crack-armor.txt
- https://ubuntu.com/blog/apparmor-vulnerability-fixes-available
- https://ubuntu.com/security/CVE-2026-23410
- https://ubuntu.com/security/notices/USN-8098-10
- https://ubuntu.com/security/notices/USN-8152-1
- https://ubuntu.com/security/notices/USN-8163-1
- https://ubuntu.com/security/notices/USN-8163-2
- https://ubuntu.com/security/notices/USN-8164-1
- https://ubuntu.com/security/notices/USN-8165-1
- https://ubuntu.com/security/notices/USN-8201-1
- https://ubuntu.com/security/notices/USN-8224-1
- https://ubuntu.com/security/notices/USN-8243-1
- https://ubuntu.com/security/notices/USN-8261-1
- https://ubuntu.com/security/notices/USN-8266-1
- https://ubuntu.com/security/notices/USN-8267-1
- https://ubuntu.com/security/vulnerabilities/crackarmor
- https://www.cve.org/CVERecord?id=CVE-2026-23410
- https://www.openwall.com/lists/oss-security/2026/04/01/3