Vulnerability identifier: #VU64201

Vulnerability risk: Low

CVSSv3.1: 6.8 [CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-31440

CWE-ID: CWE-682

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 escalate privileges on the system.

The vulnerability exists due to out-of-bounds access flaw in the Linux kernel’s implementation of the eBPF code verifier, where an incorrect register bounds calculation while checking unsigned 32-bit instructions in an eBPF program occurs. A local user can use this flaw to crash the system or possibly escalate their privileges on the system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Linux kernel:

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External links
http://www.zerodayinitiative.com/advisories/ZDI-21-503/
http://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=10bf4e83167cc68595b85fd73bb91e8f2c086e36
http://security.netapp.com/advisory/ntap-20210706-0003/
http://bugzilla.redhat.com/show_bug.cgi?id=1964028

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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.