Denial of service in curl implementation for Command Line Interface, EAV Monitors, iRules components in F5 BIG-IP products

Published: 2021-02-19 | Updated: 2023-10-28

Risk	Low
Patch available	NO
Number of vulnerabilities	1
CVE-ID	CVE-2020-8285
CWE-ID	CWE-674
Exploitation vector	Network
Public exploit	N/A
Vulnerable software Subscribe	BIG-IP DNS Hardware solutions / Routers & switches, VoIP, GSM, etc BIG-IP Link Controller Hardware solutions / Routers & switches, VoIP, GSM, etc BIG-IP AAM Hardware solutions / Routers & switches, VoIP, GSM, etc BIG-IP SSLO Hardware solutions / Firmware BIG-IP DDHD Hardware solutions / Firmware BIG-IP Hardware solutions / Firmware BIG-IP PEM Hardware solutions / Security hardware applicances BIG-IP GTM Hardware solutions / Security hardware applicances BIG-IP FPS Hardware solutions / Security hardware applicances BIG-IP ASM Hardware solutions / Security hardware applicances BIG-IP Analytics Hardware solutions / Security hardware applicances BIG-IP AFM Hardware solutions / Security hardware applicances BIG-IP LTM Hardware solutions / Security hardware applicances BIG-IP APM Hardware solutions / Security hardware applicances BIG-IP Advanced WAF Client/Desktop applications / Antivirus software/Personal firewalls
Vendor	F5 Networks

Security Bulletin

This security bulletin contains one low risk vulnerability.

1) Uncontrolled Recursion

EUVDB-ID: #VU48894

Risk: Low

CVSSv3.1: 3.8 [CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L/E:U/RL:O/RC:C]

CVE-ID: CVE-2020-8285

CWE-ID: CWE-674 - Uncontrolled Recursion

Exploit availability: No

Description

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

The vulnerability exists due tu uncontrolled recursion when processing FTP responses within the wildcard matching functionality, which allows a callback (set with <a href="https://curl.se/libcurl/c/CURLOPT_CHUNK_BGN_FUNCTION.html">CURLOPT_CHUNK_BGN_FUNCTION</a>) to return information back to libcurl on how to handle a specific entry in a directory when libcurl iterates over a list of all available entries. A remote attacker who controls the malicious FTP server can trick the victim to connect to it and crash the application, which is using the affected libcurl version.

Mitigation

Cybersecurity Help is currently unaware of any official solution to address this vulnerability.

Vulnerable software versions

BIG-IP DNS: 13.1.0 - 16.0.1.1

BIG-IP SSLO: 13.1.0 - 16.0.1.1

BIG-IP PEM: 13.1.0 - 16.0.1.1

BIG-IP Link Controller: 13.1.0 - 16.0.1.1

BIG-IP GTM: 13.1.0 - 16.0.1.1

BIG-IP FPS: 13.1.0 - 16.0.1.1

BIG-IP DDHD: 13.1.0 - 16.0.1.1

BIG-IP ASM: 13.1.0 - 16.0.1.1

BIG-IP Analytics: 13.1.0 - 16.0.1.1

BIG-IP AFM: 13.1.0 - 16.0.1.1

BIG-IP Advanced WAF: 13.1.0 - 16.0.1.1

BIG-IP AAM: 13.1.0 - 16.0.1.1

BIG-IP LTM: 13.1.0 - 16.0.1.1

BIG-IP: 13.1.0 - 16.0.1.1

BIG-IP APM: 13.1.0 - 16.0.1.1

External links

http://support.f5.com/csp/article/K61186963

Q & A

Can this vulnerability be exploited remotely?

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

How the attacker can exploit this vulnerability?

The attacker would have to send a specially crafted request to the affected device in order to exploit this vulnerability.

Is there known malware, which exploits this vulnerability?

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