CVE-2025-40287
Description
An infinite loop vulnerability was found in the exFAT filesystem driver in the Linux kernel. The exfat_find() function does not validate if dentry.stream.valid_size is negative. A malformed exFAT filesystem with such entries causes the kernel to hang during file operations like open, truncate, or write.
Statement
Mounting a maliciously crafted exFAT filesystem is required. exFAT is commonly used on removable media like SD cards and USB drives, so physical access or control over mounted media could enable this attack.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 5.5 | N/A | N/A |
| Attack Vector | Local | N/A | N/A |
| Attack Complexity | Low | N/A | N/A |
| Privileges Required | Low | N/A | N/A |
| User Interaction | None | N/A | N/A |
| Scope | Unchanged | N/A | N/A |
| Confidentiality | None | N/A | N/A |
| Integrity Impact | None | N/A | N/A |
| Availability Impact | High | N/A | N/A |
Vector
Red Hat: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Understanding the Weakness (CWE)
Integrity,Confidentiality,Availability
Technical Impact: Modify Application Data; Execute Unauthorized Code or Commands
An attacker could modify the structure of the message or data being sent to the downstream component, possibly injecting commands.
Availability
Technical Impact: DoS: Resource Consumption (Other)
in some contexts, a negative value could lead to resource consumption.
Confidentiality,Integrity
Technical Impact: Modify Memory; Read Memory
If a negative value is used to access memory, buffers, or other indexable structures, it could access memory outside the bounds of the buffer.
Frequently Asked Questions
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