CVE-2026-63815
Description
A flaw was found in the Linux kernel's f2fs (Flash-Friendly File System) component. When processing a specially crafted f2fs filesystem image, an attacker can trigger an out-of-bounds read. This occurs because the system incorrectly validates the size of inline extended attributes, leading to negative calculations that cause the system to read beyond allocated memory. This vulnerability can result in information disclosure or system instability, and may also lead to data corruption for regular files.
Understanding the Weakness (CWE)
Confidentiality
Technical Impact: Read Memory
An attacker could get secret values such as cryptographic keys, PII, memory addresses, or other information that could be used in additional attacks.
Confidentiality
Technical Impact: Bypass Protection Mechanism
Out-of-bounds memory could contain memory addresses or other information that can be used to bypass ASLR and other protection mechanisms in order to improve the reliability of exploiting a separate weakness for code execution.
Availability
Technical Impact: DoS: Crash, Exit, or Restart
An attacker could cause a segmentation fault or crash by causing memory to be read outside of the bounds of the buffer. This is especially likely when the code reads a variable amount of data and assumes that a sentinel exists to stop the read operation, such as a NUL in a string.
Other
Technical Impact: Varies by Context
The read operation could produce other undefined or unexpected results.
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