PT-2021-8128 · Linux+2 · Linux Kernel+2

Baokun Li + 1 · Published 2021-12-25 · Updated 2025-04-04 · CVE-2021-47089

Positive Technologies (AI Summary)

CVSS v2.0

4.6

Medium

Base vector

AV:L/AC:L/Au:S/C:N/I:N/A:C

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

Description The vulnerability is related to a memory leak in the Linux kernel's kfence component when using cat kfence objects. This issue can be reproduced with specific commands, including cat /sys/kernel/debug/kfence/objects, echo scan > /sys/kernel/debug/kmemleak, and cat /sys/kernel/debug/kmemleak. The leaked memory is allocated in the stack during the do syscall 64 and vfs read processes but is not released properly due to the lack of a release function corresponding to file operations in kfence. This results in a memory leak, which can potentially lead to a denial of service. The solution involves implementing the corresponding release function.

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

Memory Leak

Weakness Enumeration

CWE-401

Related Identifiers

BDU:2024-08385

CVE-2021-47089

OPENSUSE-SU-2024_2372-1

OPENSUSE-SU-2024_2394-1

SUSE-SU-2024:2372-1

SUSE-SU-2024:2394-1

SUSE-SU-2024:2939-1

Affected Products

Linux Kernel

Red Os

Suse

References · 1182

• https://osv.dev/vulnerability/DEBIAN-CVE-2021-47089 · Vendor Advisory
• https://git.kernel.org/stable/c/0129ab1f268b6cf88825eae819b9b84aa0a85634 · Patch
• https://osv.dev/vulnerability/CVE-2021-47089 · Vendor Advisory
• https://osv.dev/vulnerability/SUSE-SU-2024:2939-1 · Vendor Advisory
• https://bdu.fstec.ru/vul/2024-08385 · Security Note
• https://osv.dev/vulnerability/SUSE-SU-2024:2394-1 · Vendor Advisory
• https://ubuntu.com/security/CVE-2021-47089 · Vendor Advisory
• https://git.kernel.org/stable/c/2f06c8293d27f6337f907042c602c9c953988c48 · Patch
• https://cve.org/CVERecord?id=CVE-2021-47089 · Security Note
• https://security-tracker.debian.org/tracker/CVE-2021-47089 · Vendor Advisory
• https://osv.dev/vulnerability/UBUNTU-CVE-2021-47089 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2021-47089 · Security Note
• https://osv.dev/vulnerability/SUSE-SU-2024:2372-1 · Vendor Advisory
• https://bugzilla.suse.com/1228565 · Note
• https://bugzilla.suse.com/1226211 · Note