Vulnerabilities > CVE-2021-4155 - Incorrect Calculation of Buffer Size vulnerability in Linux Kernel
Attack vector
LOCAL Attack complexity
LOW Privileges required
LOW Confidentiality impact
HIGH Integrity impact
NONE Availability impact
NONE Summary
A data leak flaw was found in the way XFS_IOC_ALLOCSP IOCTL in the XFS filesystem allowed for size increase of files with unaligned size. A local attacker could use this flaw to leak data on the XFS filesystem otherwise not accessible to them.
Vulnerable Configurations
Common Weakness Enumeration (CWE)
Common Attack Pattern Enumeration and Classification (CAPEC)
- Overflow Buffers Buffer Overflow attacks target improper or missing bounds checking on buffer operations, typically triggered by input injected by an attacker. As a consequence, an attacker is able to write past the boundaries of allocated buffer regions in memory, causing a program crash or potentially redirection of execution as per the attackers' choice.
- Buffer Overflow via Parameter Expansion In this attack, the target software is given input that the attacker knows will be modified and expanded in size during processing. This attack relies on the target software failing to anticipate that the expanded data may exceed some internal limit, thereby creating a buffer overflow.
References
- https://access.redhat.com/security/cve/CVE-2021-4155
- https://access.redhat.com/security/cve/CVE-2021-4155
- https://bugzilla.redhat.com/show_bug.cgi?id=2034813
- https://bugzilla.redhat.com/show_bug.cgi?id=2034813
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=983d8e60f50806f90534cc5373d0ce867e5aaf79
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=983d8e60f50806f90534cc5373d0ce867e5aaf79
- https://security-tracker.debian.org/tracker/CVE-2021-4155
- https://security-tracker.debian.org/tracker/CVE-2021-4155
- https://www.openwall.com/lists/oss-security/2022/01/10/1
- https://www.openwall.com/lists/oss-security/2022/01/10/1