CVE-2021-22981

Severity: medium (CVSS 4.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.6% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-02-12 · updated 2026-06-17

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.

Affected products

F5 BIG-IP APM: from 11.6.1 through 11.6.5; from 12.1.0 through 12.1.5
BIG-IP: from 11.6.1 through 11.6.5; from 12.1.0 through 12.1.5
F5 Big-Ip Advanced Web Application Firewall: from 11.6.1 through 11.6.5; from 12.1.0 through 12.1.5
F5 Big-Ip Analytics: from 11.6.1 through 11.6.5; from 12.1.0 through 12.1.5
F5 Networks, Inc. BIG-IP (AAM): from 11.6.1 through 11.6.5; from 12.1.0 through 12.1.5
BIG-IP ASM: from 11.6.1 through 11.6.5; from 12.1.0 through 12.1.5
F5 Big-Ip Ddos Hybrid Defender: from 11.6.1 through 11.6.5; from 12.1.0 through 12.1.5
F5 BIG-IP DNS: from 11.6.1 through 11.6.5; from 12.1.0 through 12.1.5
F5 Big-Ip Fraud Protection Service: from 11.6.1 through 11.6.5; from 12.1.0 through 12.1.5
F5 Big-Ip Global Traffic Manager: from 11.6.1 through 11.6.5; from 12.1.0 through 12.1.5
F5 Big-Ip Link Controller: from 11.6.1 through 11.6.5; from 12.1.0 through 12.1.5
F5 BIG-IP (LTM): from 11.6.1 through 11.6.5; from 12.1.0 through 12.1.5
F5 Networks, Inc. BIG-IP (PEM): from 11.6.1 through 11.6.5; from 12.1.0 through 12.1.5
F5 Big-Ip Ssl Orchestrator: from 11.6.1 through 11.6.5; from 12.1.0 through 12.1.5

References

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