Vulnerabilities > CVE-2023-34256 - Out-of-bounds Read vulnerability in multiple products
Attack vector
LOCAL Attack complexity
LOW Privileges required
LOW Confidentiality impact
NONE Integrity impact
NONE Availability impact
HIGH Summary
An issue was discovered in the Linux kernel before 6.3.3. There is an out-of-bounds read in crc16 in lib/crc16.c when called from fs/ext4/super.c because ext4_group_desc_csum does not properly check an offset. NOTE: this is disputed by third parties because the kernel is not intended to defend against attackers with the stated "When modifying the block device while it is mounted by the filesystem" access.
Vulnerable Configurations
Common Weakness Enumeration (CWE)
Common Attack Pattern Enumeration and Classification (CAPEC)
- Overread Buffers An adversary attacks a target by providing input that causes an application to read beyond the boundary of a defined buffer. This typically occurs when a value influencing where to start or stop reading is set to reflect positions outside of the valid memory location of the buffer. This type of attack may result in exposure of sensitive information, a system crash, or arbitrary code execution.
References
- https://bugzilla.suse.com/show_bug.cgi?id=1211895
- https://cdn.kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.3.3
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=4f04351888a83e595571de672e0a4a8b74f4fb31
- https://lists.debian.org/debian-lts-announce/2023/07/msg00030.html
- https://lists.debian.org/debian-lts-announce/2023/10/msg00027.html
- https://syzkaller.appspot.com/bug?extid=8785e41224a3afd04321
- https://bugzilla.suse.com/show_bug.cgi?id=1211895
- https://syzkaller.appspot.com/bug?extid=8785e41224a3afd04321
- https://lists.debian.org/debian-lts-announce/2023/10/msg00027.html
- https://lists.debian.org/debian-lts-announce/2023/07/msg00030.html
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=4f04351888a83e595571de672e0a4a8b74f4fb31
- https://cdn.kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.3.3