Denial of service in libnbd

Published: 2021-03-15 | Updated: 2023-11-10

Risk	Medium
Patch available	YES
Number of vulnerabilities	1
CVE-ID	CVE-2021-20286
CWE-ID	CWE-617
Exploitation vector	Network
Public exploit	N/A
Vulnerable software	libnbd Universal components / Libraries / Libraries used by multiple products
Vendor	libguestfs

Security Bulletin

This security bulletin contains one medium risk vulnerability.

1) Reachable Assertion

EUVDB-ID: #VU82991

Risk: Medium

CVSSv4.0: 6.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2021-20286

CWE-ID: CWE-617 - Reachable Assertion

Exploit availability: No

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to a reachable assertion within the nbd_unlocked_opt_go() function in ilb/opt.c. A remote attacker can send specially crafted input to the application and perform a denial of service (DoS) attack.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

libnbd: before 1.7.3

CPE2.3

cpe:2.3:a:libguestfs:libnbd:*:*:*:*:*:*:*:*

External links

https://bugzilla.redhat.com/show_bug.cgi?id=1934727
https://gitlab.com/nbdkit/libnbd/-/commit/fb4440de9cc76e9c14bd3ddf3333e78621f40ad0

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

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