PT-2025-4324 · Linux+2 · Linux Kernel+2

Nicolas Baranger · Published 2025-01-09 · Updated 2025-10-16 · CVE-2025-21643

Positive Technologies (AI Summary)

CVSS v3.1

5.5

Medium

Base vector

AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Name of the Vulnerable Software and Affected Versions Linux kernel (affected versions not specified)

Description The issue concerns the Linux kernel's handling of kernel-initiated asynchronous Direct I/O (DIO) operations. Specifically, the netfs extract user iter() function throws a warning and fails when handling async DIO writes because it only supports IOVEC and UBUF iterators. This can be triggered by a combination of cifs and a loopback blockdev. The problem causes a write to fail and generates a warning in the syslog. The estimated number of potentially affected devices worldwide is not available. There is no information about real-world incidents where this issue was exploited.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.

Exploit

Buffer Overflow

Weakness Enumeration

CWE-120

Related Identifiers

BDU:2026-02668

CVE-2025-21643

USN-7379-1

USN-7379-2

USN-7380-1

USN-7381-1

USN-7382-1

USN-7513-1

USN-7513-2

USN-7513-3

USN-7513-4

USN-7513-5

USN-7514-1

USN-7515-1

USN-7515-2

USN-7522-1

USN-7523-1

USN-7524-1

Affected Products

Linuxmint

Linux Kernel

Ubuntu

References · 822

• 🔥 https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/21xxx/CVE-2025-21643.json · Exploit
• https://ubuntu.com/security/CVE-2024-53166 · Vendor Advisory
• https://ubuntu.com/security/CVE-2024-56639 · Vendor Advisory
• https://ubuntu.com/security/CVE-2024-50059 · Vendor Advisory
• https://ubuntu.com/security/CVE-2024-56602 · Vendor Advisory
• https://ubuntu.com/security/CVE-2024-56594 · Vendor Advisory
• https://ubuntu.com/security/CVE-2024-50185 · Vendor Advisory
• https://ubuntu.com/security/CVE-2024-50249 · Vendor Advisory
• https://ubuntu.com/security/CVE-2024-50211 · Vendor Advisory
• https://ubuntu.com/security/CVE-2024-50205 · Vendor Advisory
• https://ubuntu.com/security/CVE-2024-50151 · Vendor Advisory
• https://ubuntu.com/security/CVE-2024-50145 · Vendor Advisory
• https://ubuntu.com/security/CVE-2024-57791 · Vendor Advisory
• https://ubuntu.com/security/CVE-2024-57799 · Vendor Advisory
• https://ubuntu.com/security/CVE-2024-50086 · Vendor Advisory