PT-2024-11230 · Linux+3 · Linux Kernel+3

Lin + 2 · Published 2021-06-16 · Updated 2024-05-21 · CVE-2021-47221

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 is related to the SLUB redzoning feature in the Linux kernel, which checks for corruption from s->object size instead of s->inuse. This can cause the freelist pointer to be written beyond s->object size when the object size is less than 24, corrupting the redzone. The problem is visible when using "slub debug=ZF". The kernel adjusts the offset to stay within s->object size to resolve the issue. No caches in this size range are known to exist in the kernel currently.

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

Memory Corruption

Weakness Enumeration

CWE-763

CWE-787

Related Identifiers

BDU:2025-13715

CESA-2023_2951

CVE-2021-47221

RHSA-2023:2951

RHSA-2023_2951

Affected Products

Astra Linux

Centos

Linux Kernel

Red Hat

References · 17

• https://cve.org/CVERecord?id=CVE-2021-47221 · Security Note
• https://ubuntu.com/security/CVE-2021-47221 · Vendor Advisory
• https://git.kernel.org/stable/c/f6ed2357541612a13a5841b3af4dc32ed984a25f · Patch
• https://osv.dev/vulnerability/UBUNTU-CVE-2021-47221 · Vendor Advisory
• https://osv.dev/vulnerability/DEBIAN-CVE-2021-47221 · Vendor Advisory
• https://git.kernel.org/stable/c/ce6e8bee7a3883e8008b30f5887dbb426aac6a35 · Patch
• https://osv.dev/vulnerability/CVE-2021-47221 · Vendor Advisory
• https://bdu.fstec.ru/vul/2025-13715 · Security Note
• https://nvd.nist.gov/vuln/detail/CVE-2021-47221 · Security Note
• https://security-tracker.debian.org/tracker/CVE-2021-47221 · Vendor Advisory
• https://git.kernel.org/stable/c/e41a49fadbc80b60b48d3c095d9e2ee7ef7c9a8e · Patch
• https://lore.kernel.org/linux-cve-announce/2024052135-CVE-2021-47221-4e17@gregkh · Note
• https://git.kernel.org/linus/e41a49fadbc80b60b48d3c095d9e2ee7ef7c9a8e · Note
• https://kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.10.46 · Note
• https://t.me/cvenotify/80588 · Telegram Post