CVE-2026-64063
Description
A flaw was found in the Linux kernel's netfs component. This vulnerability occurs when the netfslib performs a 'streaming write' where dirty data is stored directly into folios without prior reading. If a partially written streaming write page is entirely or partially overwritten by a subsequent write operation, the system may not correctly handle the dirty data, leading to data integrity issues. This could allow an attacker to cause data corruption.
Statement
This vulnerability is rated as Moderate severity because it requires local user access to execute specific overlapping write operations on netfslib-backed network filesystems, confining the potential impact to data corruption or denial of service without exposing confidential information. Exploitation depends on active write workloads on network filesystems configured with netfs streaming writes. Earlier releases such as Red Hat Enterprise Linux 8 and 9 are not affected because they do not contain the vulnerable folio streaming write implementation.
Mitigation
Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
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 | 7.8 | N/A |
| Attack Vector | Local | Local | N/A |
| Attack Complexity | Low | Low | N/A |
| Privileges Required | Low | Low | N/A |
| User Interaction | None | None | N/A |
| Scope | Unchanged | Unchanged | N/A |
| Confidentiality | None | High | N/A |
| Integrity Impact | None | High | N/A |
| Availability Impact | High | High | N/A |
Vector
Red Hat: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
NVD: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
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