#VU67181 Information disclosure in Linux kernel - CVE-2021-31829

Vulnerability identifier: #VU67181

Vulnerability risk: Low

CVSSv4.0: 4.3 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-31829

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 Linux kernel's eBPF verification code. A local user can insert eBPF instructions, use the eBPF verifier to abuse a spectre-like flaw and infer all system memory.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Linux kernel: All versions

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External links
https://www.openwall.com/lists/oss-security/2021/05/04/4
https://github.com/torvalds/linux/commit/801c6058d14a82179a7ee17a4b532cac6fad067f

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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.