#VU50610 Out-of-bounds write in F5 Networks products - CVE-2021-22973

Vulnerability identifier: #VU50610

Vulnerability 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-2021-22973

CWE-ID: CWE-787

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 a boundary error within the JSON parser function in iRules LX component. A remote attacker can pass specially crafted data with iRules LX commands to the system, trigger out-of-bounds write and crash the Traffic Management Microkernel (TMM) module.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

BIG-IP: 12.1.0 HF1 - 12.1.5.2, 13.1.0 - 13.1.3.4, 14.1.0 - 14.1.3, 15.1.0 - 15.1.1, 16.0.0 - 16.0.1

BIG-IP LTM: 12.1.0 HF1 - 16.0.1

BIG-IP AAM: 12.1.0 HF1 - 16.0.1

BIG-IP AFM: 12.1.0 HF1 - 16.0.1

BIG-IP Analytics: 12.1.0 - 16.0.1

BIG-IP APM: 12.1.0 HF1 - 16.0.1

BIG-IP ASM: 12.1.0 HF1 - 16.0.1

BIG-IP DNS: 12.1.0 - 16.0.1

BIG-IP FPS: 12.1.0 - 16.0.1

BIG-IP GTM: 12.1.0 - 16.0.1

BIG-IP Link Controller: 12.1.0 HF1 - 16.0.1

BIG-IP PEM: 12.1.0 HF1 - 16.0.1

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External links
https://support.f5.com/csp/article/K13323323

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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.