High severity · published Mar 31, 2021
CVE-2021-23000
On BIG-IP versions 13.1.3.4-13.1.3.6 and 12.1.5.2, if the tmm.http.rfc.enforcement BigDB key is enabled in a BIG-IP system, or the Bad host header value is checked in the AFM HTTP…
7.5
CVSS
1%
EPSS
No
On KEV
Description
On BIG-IP versions 13.1.3.4-13.1.3.6 and 12.1.5.2, if the tmm.http.rfc.enforcement BigDB key is enabled in a BIG-IP system, or the Bad host header value is checked in the AFM HTTP security profile associated with a virtual server, in rare instances, a specific sequence of malicious requests may cause TMM to restart. Note: Software versions which have reached End of Software Development (EoSD) are not evaluated.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.0% · higher than 62% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
BA
Big-ip Access Policy Manager · F5
13.1.3.4 before 13.1.3.6; 12.1.5.2 · source: NVD
BA
Big-ip Advanced Firewall Manager · F5
13.1.3.4 before 13.1.3.6; 12.1.5.2 · source: NVD
BA
Big-ip Advanced Web Application Firewall · F5
13.1.3.4 before 13.1.3.6; 12.1.5.2 · source: NVD
BA
Big-ip Analytics · F5
13.1.3.4 before 13.1.3.6; 12.1.5.2 · source: NVD
BA
Big-ip Application Acceleration Manager · F5
13.1.3.4 before 13.1.3.6; 12.1.5.2 · source: NVD
BA
Big-ip Application Security Manager · F5
13.1.3.4 before 13.1.3.6; 12.1.5.2 · source: NVD
BD
Big-ip Ddos Hybrid Defender · F5
13.1.3.4 before 13.1.3.6; 12.1.5.2 · source: NVD
BD
Big-ip Domain Name System · F5
13.1.3.4 before 13.1.3.6; 12.1.5.2 · source: NVD
BF
Big-ip Fraud Protection Service · F5
13.1.3.4 before 13.1.3.6; 12.1.5.2 · source: NVD
BG
Big-ip Global Traffic Manager · F5
13.1.3.4 before 13.1.3.6; 12.1.5.2 · source: NVD
BL
Big-ip Link Controller · F5
13.1.3.4 before 13.1.3.6; 12.1.5.2 · source: NVD
BL
Big-ip Local Traffic Manager · F5
13.1.3.4 before 13.1.3.6; 12.1.5.2 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-23000
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-23000
Vendor Advisory
https://support.f5.com/csp/article/K34441555
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