Medium severity · published Feb 12, 2021
CVE-2021-22981
On all versions of BIG-IP 12.1.x and 11.6.x, the original TLS protocol includes a weakness in the master secret negotiation that is mitigated by the Extended Master Secret (EMS)…
4.8
CVSS
0.6%
EPSS
No
On KEV
Description
On all versions of BIG-IP 12.1.x and 11.6.x, the original TLS protocol includes a weakness in the master secret negotiation that is mitigated by the Extended Master Secret (EMS) extension defined in RFC 7627. TLS connections that do not use EMS are vulnerable to man-in-the-middle attacks during renegotiation. Note: Software versions which have reached End of Software Development (EoSD) are not evaluated.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.6% · higher than 46% 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
11.6.1 through 11.6.5; 12.1.0 through 12.1.5 · source: NVD
BA
Big-ip Advanced Firewall Manager · F5
11.6.1 through 11.6.5; 12.1.0 through 12.1.5 · source: NVD
BA
Big-ip Advanced Web Application Firewall · F5
11.6.1 through 11.6.5; 12.1.0 through 12.1.5 · source: NVD
BA
Big-ip Analytics · F5
11.6.1 through 11.6.5; 12.1.0 through 12.1.5 · source: NVD
BA
Big-ip Application Acceleration Manager · F5
11.6.1 through 11.6.5; 12.1.0 through 12.1.5 · source: NVD
BA
Big-ip Application Security Manager · F5
11.6.1 through 11.6.5; 12.1.0 through 12.1.5 · source: NVD
BD
Big-ip Ddos Hybrid Defender · F5
11.6.1 through 11.6.5; 12.1.0 through 12.1.5 · source: NVD
BD
Big-ip Domain Name System · F5
11.6.1 through 11.6.5; 12.1.0 through 12.1.5 · source: NVD
BF
Big-ip Fraud Protection Service · F5
11.6.1 through 11.6.5; 12.1.0 through 12.1.5 · source: NVD
BG
Big-ip Global Traffic Manager · F5
11.6.1 through 11.6.5; 12.1.0 through 12.1.5 · source: NVD
BL
Big-ip Link Controller · F5
11.6.1 through 11.6.5; 12.1.0 through 12.1.5 · source: NVD
BL
Big-ip Local Traffic Manager · F5
11.6.1 through 11.6.5; 12.1.0 through 12.1.5 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-22981
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-22981
Vendor Advisory
https://support.f5.com/csp/article/K09121542
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