PT-2025-7947 · Linux+3 · Linux Kernel+3

Chengsong Ke · Published 2025-02-26 · Updated 2025-05-21 · CVE-2021-47636

Positive Technologies (AI Summary)

CVSS v3.1

7.1

High

Base vector

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

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

Description A read out-of-bounds issue has been identified in the ubifs wbuf write nolock() function of the Linux kernel. This issue can occur when the len parameter is not 8-byte aligned, potentially leading to accessing buf out of bounds. The problem arises in the ubifs wbuf write nolock() function when it attempts to write data to the leb safely, without properly handling the length of the data read from buf. This issue can be detected by KASAN, which reports a slab-out-of-bounds error.

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

Exploit

Out of bounds Read

Weakness Enumeration

CWE-125

Related Identifiers

CVE-2021-47636

SUSE-SU-2025:1027-1

SUSE-SU-2025:1176-1

SUSE-SU-2025:1183-1

SUSE-SU-2025:1241-1

SUSE-SU-2025_1027-1

SUSE-SU-2025_1241-1

Affected Products

Astra Linux

Linux Kernel

Red Os

Suse

References · 1336

• 🔥 https://github.com/rapid7/metasploit-framework/blob/master/modules/exploits/linux/local/cve_2022_0995_watch_queue.rb · Exploit
• 🔥 https://github.com/qazbnm456/awesome-cve-poc/blob/master/CVE-2017-5753.md · Exploit
• 🔥 https://github.com/Bonfee/CVE-2022-0995 · Exploit
• 🔥 https://github.com/TurtleARM/CVE-2023-0179-PoC · Exploit
• 🔥 https://github.com/H4K6/CVE-2023-0179-PoC · Exploit
• 🔥 https://github.com/EdwardOwusuAdjei/Spectre-PoC · Exploit
• https://osv.dev/vulnerability/SUSE-SU-2025:1027-1 · Vendor Advisory
• https://osv.dev/vulnerability/DEBIAN-CVE-2021-47636 · Vendor Advisory
• https://git.kernel.org/stable/c/5343575aa11c5d7044107d59d43f84aec01312b0 · Patch
• https://security-tracker.debian.org/tracker/CVE-2021-47636 · Vendor Advisory
• https://git.kernel.org/stable/c/a7054aaf1909cf40489c0ec1b728fdcf79c751a6 · Patch
• https://osv.dev/vulnerability/SUSE-SU-2025:1241-1 · Vendor Advisory
• https://osv.dev/vulnerability/CVE-2021-47636 · Vendor Advisory
• https://osv.dev/vulnerability/SUSE-SU-2025:1176-1 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2021-47636 · Security Note