Vulnerability identifier: #VU51394

Vulnerability risk: Medium

CVSSv3.1: 6.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-22999

CWE-ID: CWE-399

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
BIG-IP
Hardware solutions / Firmware
BIG-IP LTM
Hardware solutions / Security hardware applicances
BIG-IP AFM
Hardware solutions / Security hardware applicances
BIG-IP Analytics
Hardware solutions / Security hardware applicances
BIG-IP APM
Hardware solutions / Security hardware applicances
BIG-IP ASM
Hardware solutions / Security hardware applicances
BIG-IP FPS
Hardware solutions / Security hardware applicances
BIG-IP GTM
Hardware solutions / Security hardware applicances
BIG-IP PEM
Hardware solutions / Security hardware applicances
BIG-IP AAM
Hardware solutions / Routers & switches, VoIP, GSM, etc
BIG-IP DNS
Hardware solutions / Routers & switches, VoIP, GSM, etc
BIG-IP Link Controller
Hardware solutions / Routers & switches, VoIP, GSM, etc

Vendor: F5 Networks

Description

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

The vulnerability exists due to improper management of internal resources within the HTTP/2 Profile feature when processing aborted connections for HTTP/2 requests. A remote attacker can send multiple HTTP/2 requests and permanently close connections, which leads to a denial of service (DoS) condition, as the BIG-IP system indefinitely retains such streams unclosed.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

BIG-IP: 15.0.0 - 15.0.1.4, 14.1.0 - 14.1.3.1

BIG-IP LTM: 14.1.0 - 15.0.1.4

BIG-IP AAM: 14.1.0 - 15.0.1.4

BIG-IP AFM: 14.1.0 - 15.0.1.4

BIG-IP Analytics: 14.1.0 - 15.0.1.4

BIG-IP APM: 14.1.0 - 15.0.1.4

BIG-IP ASM: 14.1.0 - 15.0.1.4

BIG-IP DNS: 14.1.0 - 15.0.1.4

BIG-IP FPS: 14.1.0 - 15.0.1.4

BIG-IP GTM: 14.1.0 - 15.0.1.4

BIG-IP Link Controller: 14.1.0 - 15.0.1.4

BIG-IP PEM: 14.1.0 - 15.0.1.4

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External links
http://support.f5.com/csp/article/K02333782

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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.