THE THREAT
On March 10th, 2021, F5 announced multiple critical vulnerabilities impacting their BIG-IP and BIG-IQ products. In total, seven vulnerabilities were disclosed, four of which allow Remote Code Execution if exploited. These high-impact vulnerabilities are likely to be targeted by threat actors in the near future.
To date, there is no indication that these vulnerabilities have been involved in real world attacks. Due to the prevalence of BIG-IP and BIG-IQ products, along with the criticality of the vulnerabilities, it is likely that exploitation will occur in the near future. Organizations are strongly recommended to apply the related security patches as soon as possible.
What we’re doing about it
- MVS will automatically add the relevant plugins for these vulnerabilities once details are made available
- eSentire security teams continue to track this topic and additional detection measures are currently under review
What you should do about it
- After performing a business impact review, apply the relevant security patches provided by F5
- If patching is currently not possible, workarounds are available for all vulnerabilities excluding CVE-2021-22991
Additional information
In total, F5 released security patches for seven separate vulnerabilities. Four are classified as critical, while two are ranked as high, and the final vulnerability is medium. See the following list for vulnerability details.
CVE-2021-22987 [CVSS: 9.9]: RCE vulnerability impacting BIG-IP systems (LTM, AAM, Advanced WAF, AFM, Analytics, APM, ASM, DDHD, DNS, FPS, GTM, Link Controller, PEM, SSLO). Exploitation requires authentication.
CVE-2021-22986 [CVSS: 9.8]: An unauthenticated remote code execution vulnerability. Exploitation would allow a remote unauthenticated attack to execute system commands, create/delete files, and disable services. This vulnerability impacts BIG-IP systems (LTM, AAM, Advanced WAF, AFM, Analytics, APM, ASM, DDHD, DNS, FPS, GTM, Link Controller, PEM, SSLO) and the BIG-IQ Centralized Management system.
CVE-2021-22991 [CVSS: 9.0]: A buffer overflow vulnerability that may result in Denial of Service (DoS) or RCE. The vulnerability impacts BIG-IP systems (LTM, AAM, Advanced WAF, AFM, Analytics, APM, ASM, DDHD, DNS, FPS, GTM, Link Controller, PEM, SSLO). In an attack scenario, threat actors could exploit this vulnerability by sending requests to a virtual server. Authentication is not required.
CVE-2021-22992 [CVSS: 9.0]: A buffer overflow vulnerability that may result in DoS or RCE. Systems vulnerable include the GIG-IP Advanced Web Application Firewall (WAF) and the BIG-IP Application Security Manager. In order to exploit this vulnerability, a threat actor would require previous access.
CVE-2021-22988 [CVSS: 8.8] An authenticated RCE vulnerability. The vulnerability impacts BIG-IP systems (LTM, AAM, Advanced WAF, AFM, Analytics, APM, ASM, DDHD, DNS, FPS, GTM, Link Controller, PEM, SSLO). An already authenticated attacker with network access to the Configuration utility may exploit this vulnerability to cause code execution, create or delete files, and disable services.
CVE-21021-22989 [CVSS: 8.0] An authenticated remote command execution vulnerability. The vulnerability affects BIG-IP systems (Advanced WAF and ASM). In order to exploit this vulnerability, the attacker would need to have already compromised a highly privilege user account.
CVE-21021-22990 [CVSS: 6.6] An authenticated RCE vulnerability. The vulnerability impacts BIG-IP systems (Advanced WAF and ASM). In order to exploit this vulnerability, the attacker would need to have already compromised a highly privilege user account.
References:
[1] https://support.f5.com/csp/article/K02566623
