#VU91558 Improper Initialization in Linux kernel - CVE-2021-29648

Vulnerability identifier: #VU91558

Vulnerability risk: Low

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

CVE-ID: CVE-2021-29648

CWE-ID: CWE-665

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 perform a denial of service (DoS) attack.

The vulnerability exists due to improper initialization within the check_btf_info() function in kernel/bpf/verifier.c, within the map_create() function in kernel/bpf/syscall.c. A local user can perform a denial of service (DoS) attack.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Linux kernel: All versions

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External links
https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.11.11
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=350a5c4dd2452ea999cc5e1d4a8dbf12de2f97ef
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/RZGMUP6QEHJJEKPMLKOSPWYMW7PXFC2M/
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/VTADK5ELGTATGW2RK3K5MBJ2WGYCPZCM/
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/WKRNELXLVFDY6Y5XDMWLIH3VKIMQXLLR/

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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.