Vulnerabilities > CVE-2024-39480 - Classic Buffer Overflow vulnerability in Linux Kernel
Summary
In the Linux kernel, the following vulnerability has been resolved: kdb: Fix buffer overflow during tab-complete Currently, when the user attempts symbol completion with the Tab key, kdb will use strncpy() to insert the completed symbol into the command buffer. Unfortunately it passes the size of the source buffer rather than the destination to strncpy() with predictably horrible results. Most obviously if the command buffer is already full but cp, the cursor position, is in the middle of the buffer, then we will write past the end of the supplied buffer. Fix this by replacing the dubious strncpy() calls with memmove()/memcpy() calls plus explicit boundary checks to make sure we have enough space before we start moving characters around.
Vulnerable Configurations
Common Weakness Enumeration (CWE)
Common Attack Pattern Enumeration and Classification (CAPEC)
- Buffer Overflow via Environment Variables This attack pattern involves causing a buffer overflow through manipulation of environment variables. Once the attacker finds that they can modify an environment variable, they may try to overflow associated buffers. This attack leverages implicit trust often placed in environment variables.
- 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.
- Client-side Injection-induced Buffer Overflow This type of attack exploits a buffer overflow vulnerability in targeted client software through injection of malicious content from a custom-built hostile service.
- Filter Failure through Buffer Overflow In this attack, the idea is to cause an active filter to fail by causing an oversized transaction. An attacker may try to feed overly long input strings to the program in an attempt to overwhelm the filter (by causing a buffer overflow) and hoping that the filter does not fail securely (i.e. the user input is let into the system unfiltered).
- MIME Conversion An attacker exploits a weakness in the MIME conversion routine to cause a buffer overflow and gain control over the mail server machine. The MIME system is designed to allow various different information formats to be interpreted and sent via e-mail. Attack points exist when data are converted to MIME compatible format and back.
References
- https://git.kernel.org/stable/c/fb824a99e148ff272a53d71d84122728b5f00992
- https://git.kernel.org/stable/c/ddd2972d8e2dee3b33e8121669d55def59f0be8a
- https://git.kernel.org/stable/c/cfdc2fa4db57503bc6d3817240547c8ddc55fa96
- https://git.kernel.org/stable/c/f636a40834d22e5e3fc748f060211879c056cd33
- https://git.kernel.org/stable/c/33d9c814652b971461d1e30bead6792851c209e7
- https://git.kernel.org/stable/c/107e825cc448b7834b31e8b1b3cf0f57426d46d5
- https://git.kernel.org/stable/c/f694da720dcf795dc3eb97bf76d220213f76aaa7
- https://git.kernel.org/stable/c/e9730744bf3af04cda23799029342aa3cddbc454