UBUNTU-CVE-2025-38685
In the Linux kernel, the following vulnerability has been resolved: fbdev: Fix vmalloc out-of-bounds write in fast_imageblit This issue triggers when a userspace program does an ioctl FBIOPUT_CON2FBMAP by passing console number and frame buffer number. Ideally this maps console to frame buffer and updates the screen if console is visible. As part of mapping it has to do resize of console according to frame buffer info. if this resize fails and returns from vc_do_resize() and continues further. At this point console and new frame buffer are mapped and sets display vars. Despite failure still it continue to proceed updating the screen at later stages where vc_data is related to previous frame buffer and frame buffer info and display vars are mapped to new frame buffer and eventully leading to out-of-bounds write in fast_imageblit(). This bheviour is excepted only when fg_console is equal to requested console which is a visible console and updates screen with invalid struct references in fbcon_putcs().
02 / AFFECTED SOFTWARE
Affected packages
11 explicit affected versions
53 explicit affected versions
116 explicit affected versions
75 explicit affected versions
50 explicit affected versions
6 explicit affected versions
12 explicit affected versions
19 explicit affected versions
10 explicit affected versions
6 explicit affected versions
85 explicit affected versions
24 explicit affected versions
70 explicit affected versions
70 explicit affected versions
91 explicit affected versions
76 explicit affected versions
65 explicit affected versions
10 explicit affected versions
28 explicit affected versions
26 explicit affected versions
77 explicit affected versions
191 explicit affected versions
7 explicit affected versions
74 explicit affected versions
32 explicit affected versions
13 explicit affected versions
85 explicit affected versions
35 explicit affected versions
35 explicit affected versions
37 explicit affected versions
35 explicit affected versions
18 explicit affected versions
32 explicit affected versions
118 explicit affected versions
64 explicit affected versions
37 explicit affected versions
120 explicit affected versions
13 explicit affected versions
4 explicit affected versions
121 explicit affected versions
23 explicit affected versions
43 explicit affected versions
124 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
76 explicit affected versions
39 explicit affected versions
8 explicit affected versions
7 explicit affected versions
12 explicit affected versions
11 explicit affected versions
111 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
104 explicit affected versions
12 explicit affected versions
105 explicit affected versions
12 explicit affected versions
32 explicit affected versions
120 explicit affected versions
31 explicit affected versions
16 explicit affected versions
23 explicit affected versions
25 explicit affected versions
10 explicit affected versions
37 explicit affected versions
10 explicit affected versions
13 explicit affected versions
31 explicit affected versions
3 explicit affected versions
10 explicit affected versions
11 explicit affected versions
52 explicit affected versions
1 explicit affected versions
26 explicit affected versions
3 explicit affected versions
13 explicit affected versions
144 explicit affected versions
24 explicit affected versions
1 explicit affected versions
29 explicit affected versions
111 explicit affected versions
13 explicit affected versions
12 explicit affected versions
82 explicit affected versions
32 explicit affected versions
32 explicit affected versions
1 explicit affected versions
100 explicit affected versions
77 explicit affected versions
40 explicit affected versions
33 explicit affected versions
23 explicit affected versions
46 explicit affected versions
10 explicit affected versions
11 explicit affected versions
188 explicit affected versions
10 explicit affected versions
11 explicit affected versions
5 explicit affected versions
12 explicit affected versions
7 explicit affected versions
12 explicit affected versions
138 explicit affected versions
2 explicit affected versions
5 explicit affected versions
62 explicit affected versions
132 explicit affected versions
78 explicit affected versions
165 explicit affected versions
154 explicit affected versions
10 explicit affected versions
26 explicit affected versions
31 explicit affected versions
1 explicit affected versions
54 explicit affected versions
26 explicit affected versions
38 explicit affected versions
11 explicit affected versions
13 explicit affected versions
37 explicit affected versions
139 explicit affected versions
78 explicit affected versions
16 explicit affected versions
76 explicit affected versions
41 explicit affected versions
116 explicit affected versions
3 explicit affected versions
132 explicit affected versions
93 explicit affected versions
1 explicit affected versions
7 explicit affected versions
2 explicit affected versions
51 explicit affected versions
92 explicit affected versions
18 explicit affected versions
33 explicit affected versions
12 explicit affected versions
64 explicit affected versions
65 explicit affected versions
27 explicit affected versions
51 explicit affected versions
121 explicit affected versions
1 explicit affected versions
1 explicit affected versions
98 explicit affected versions
34 explicit affected versions
8 explicit affected versions
42 explicit affected versions
5 explicit affected versions
3 explicit affected versions
8 explicit affected versions
1 explicit affected versions
10 explicit affected versions
7 explicit affected versions
37 explicit affected versions
13 explicit affected versions
110 explicit affected versions
13 explicit affected versions
72 explicit affected versions
7 explicit affected versions
140 explicit affected versions
8 explicit affected versions
94 explicit affected versions
10 explicit affected versions
12 explicit affected versions
9 explicit affected versions
25 explicit affected versions
108 explicit affected versions
80 explicit affected versions
56 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
42 explicit affected versions
14 explicit affected versions
38 explicit affected versions
167 explicit affected versions
9 explicit affected versions
11 explicit affected versions
30 explicit affected versions
13 explicit affected versions
78 explicit affected versions
8 explicit affected versions
7 explicit affected versions
97 explicit affected versions
121 explicit affected versions
4 explicit affected versions
67 explicit affected versions
1 explicit affected versions
1 explicit affected versions
1 explicit affected versions
76 explicit affected versions
67 explicit affected versions
66 explicit affected versions
13 explicit affected versions
43 explicit affected versions
77 explicit affected versions
119 explicit affected versions
10 explicit affected versions
8 explicit affected versions
36 explicit affected versions
88 explicit affected versions
14 explicit affected versions
4 explicit affected versions
78 explicit affected versions
11 explicit affected versions
1 explicit affected versions
69 explicit affected versions
123 explicit affected versions
10 explicit affected versions
30 explicit affected versions
66 explicit affected versions
03 / CONNECTIONS
Connected vulnerabilities
04 / EVIDENCE
Source records
In the Linux kernel, the following vulnerability has been resolved: fbdev: Fix vmalloc out-of-bounds write in fast_imageblit This issue triggers when a userspace program does an ioctl FBIOPUT_CON2FBMAP by passing console number and frame buffer number. Ideally this maps console to frame buffer and updates the screen if console is visible. As part of mapping it has to do resize of console according to frame buffer info. if this resize fails and returns from vc_do_resize() and continues further. At this point console and new frame buffer are mapped and sets display vars. Despite failure still it continue to proceed updating the screen at later stages where vc_data is related to previous frame buffer and frame buffer info and display vars are mapped to new frame buffer and eventully leading to out-of-bounds write in fast_imageblit(). This bheviour is excepted only when fg_console is equal to requested console which is a visible console and updates screen with invalid struct references in fbcon_putcs().
05 / REFERENCES
Further evidence
- https://git.kernel.org/linus/af0db3c1f898144846d4c172531a199bb3ca375d
- https://git.kernel.org/stable/c/078e62bffca4b7e72e8f3550eb063ab981c36c7a
- https://git.kernel.org/stable/c/27b118aebdd84161c8ff5ce49d9d536f2af10754
- https://git.kernel.org/stable/c/4c4d7ddaf1d43780b106bedc692679f965dc5a3a
- https://git.kernel.org/stable/c/56701bf9eeb63219e378cb7fcbd066ea4eaeeb50
- https://git.kernel.org/stable/c/af0db3c1f898144846d4c172531a199bb3ca375d
- https://git.kernel.org/stable/c/cfec17721265e72e50cc69c6004fe3475cd38df2
- https://git.kernel.org/stable/c/ed9b8e5016230868c8d813d9179523f729fec8c6
- https://ubuntu.com/security/CVE-2025-38685
- https://ubuntu.com/security/notices/USN-7909-1
- https://ubuntu.com/security/notices/USN-7909-2
- https://ubuntu.com/security/notices/USN-7909-3
- https://ubuntu.com/security/notices/USN-7909-4
- https://ubuntu.com/security/notices/USN-7909-5
- https://ubuntu.com/security/notices/USN-7910-1
- https://ubuntu.com/security/notices/USN-7910-2
- https://ubuntu.com/security/notices/USN-7933-1
- https://ubuntu.com/security/notices/USN-7938-1
- https://ubuntu.com/security/notices/USN-8028-1
- https://ubuntu.com/security/notices/USN-8028-2
- https://ubuntu.com/security/notices/USN-8028-3
- https://ubuntu.com/security/notices/USN-8028-4
- https://ubuntu.com/security/notices/USN-8028-5
- https://ubuntu.com/security/notices/USN-8028-6
- https://ubuntu.com/security/notices/USN-8028-7
- https://ubuntu.com/security/notices/USN-8028-8
- https://ubuntu.com/security/notices/USN-8031-1
- https://ubuntu.com/security/notices/USN-8031-2
- https://ubuntu.com/security/notices/USN-8031-3
- https://ubuntu.com/security/notices/USN-8052-1
- https://ubuntu.com/security/notices/USN-8052-2
- https://ubuntu.com/security/notices/USN-8074-1
- https://ubuntu.com/security/notices/USN-8074-2
- https://ubuntu.com/security/notices/USN-8126-1
- https://www.cve.org/CVERecord?id=CVE-2025-38685