Vulnerabilities > CVE-2023-1295 - Time-of-check Time-of-use (TOCTOU) Race Condition vulnerability in multiple products
Attack vector
LOCAL Attack complexity
HIGH Privileges required
LOW Confidentiality impact
HIGH Integrity impact
HIGH Availability impact
HIGH Summary
A time-of-check to time-of-use issue exists in io_uring subsystem's IORING_OP_CLOSE operation in the Linux kernel's versions 5.6 - 5.11 (inclusive), which allows a local user to elevate their privileges to root. Introduced in b5dba59e0cf7e2cc4d3b3b1ac5fe81ddf21959eb, patched in 9eac1904d3364254d622bf2c771c4f85cd435fc2, backported to stable in 788d0824269bef539fe31a785b1517882eafed93.
Vulnerable Configurations
Common Weakness Enumeration (CWE)
Common Attack Pattern Enumeration and Classification (CAPEC)
- Leveraging Race Conditions via Symbolic Links This attack leverages the use of symbolic links (Symlinks) in order to write to sensitive files. An attacker can create a Symlink link to a target file not otherwise accessible to her. When the privileged program tries to create a temporary file with the same name as the Symlink link, it will actually write to the target file pointed to by the attackers' Symlink link. If the attacker can insert malicious content in the temporary file she will be writing to the sensitive file by using the Symlink. The race occurs because the system checks if the temporary file exists, then creates the file. The attacker would typically create the Symlink during the interval between the check and the creation of the temporary file.
- Leveraging Time-of-Check and Time-of-Use (TOCTOU) Race Conditions This attack targets a race condition occurring between the time of check (state) for a resource and the time of use of a resource. The typical example is the file access. The attacker can leverage a file access race condition by "running the race", meaning that he would modify the resource between the first time the target program accesses the file and the time the target program uses the file. During that period of time, the attacker could do something such as replace the file and cause an escalation of privilege.
References
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=788d0824269bef539fe31a785b1517882eafed93
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=788d0824269bef539fe31a785b1517882eafed93
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=9eac1904d3364254d622bf2c771c4f85cd435fc2
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=9eac1904d3364254d622bf2c771c4f85cd435fc2
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b5dba59e0cf7e2cc4d3b3b1ac5fe81ddf21959eb
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b5dba59e0cf7e2cc4d3b3b1ac5fe81ddf21959eb
- https://kernel.dance/788d0824269bef539fe31a785b1517882eafed93
- https://kernel.dance/788d0824269bef539fe31a785b1517882eafed93
- https://kernel.dance/9eac1904d3364254d622bf2c771c4f85cd435fc2
- https://kernel.dance/9eac1904d3364254d622bf2c771c4f85cd435fc2
- https://security.netapp.com/advisory/ntap-20230731-0006/
- https://security.netapp.com/advisory/ntap-20230731-0006/