#VU54395 Information disclosure in Linux kernel - CVE-2021-21781

Vulnerability identifier: #VU54395

Vulnerability risk: Low

CVSSv4.0: 1.1 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-21781

CWE-ID: CWE-200

Exploitation vector: Local

Exploit availability: No

Vulnerable software:
Linux kernel
Operating systems & Components / Operating system

Vendor: Linux Foundation

Description

The vulnerability allows a local user to gain access to potentially sensitive information.

The vulnerability exists due to excessive data output in the ARM SIGPAGE functionality. A userland application can read the contents of the sigpage, which can leak kernel memory contents.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Linux kernel: before 4.14.222, 4.19.177, 5.4.99, 5.10.17, 5.11, 4.14.222, 4.14.222, 4.14.222

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External links
http://www.talosintelligence.com/vulnerability_reports/TALOS-2021-1243

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Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.