CVE-2021-23009

Home/CVE/On BIG-IP version 16.0.x before 16.0.1.1 and 15.1.x before 15.1.3, malformed HTTP/2 requests may cause an infinite loop

CVE

On BIG-IP version 16.0.x before 16.0.1.1 and 15.1.x before 15.1.3, malformed HTTP/2 requests may cause an infinite loop

On BIG-IP version 16.0.x before 16.0.1.1 and 15.1.x before 15.1.3, malformed HTTP/2 requests may cause an infinite loop which causes a Denial of Service for Data Plane traffic. TMM takes the configured HA action when the TMM process is aborted. There is no control plane exposure, this is a data plane issue only.

Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

HIGH · CVSS 7.5 EPSS 0.00647

Schedule remediation

CVSS base score ≥ 7.0

Sigma rules0 YARA rules0

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Weakness Classification

CWE-835Loop with Unreachable Exit Condition ('Infinite Loop')

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Affected Products & Versions

f5 big-ip access policy manager>= 15.1.0 and < 15.1.3
f5 big-ip access policy manager>= 16.0.0 and < 16.0.1.1
f5 big-ip advanced firewall manager>= 15.1.0 and < 15.1.3
f5 big-ip advanced firewall manager>= 16.0.0 and < 16.0.1.1
f5 big-ip advanced web application firewall>= 15.1.0 and < 15.1.3
f5 big-ip advanced web application firewall>= 16.0.0 and < 16.0.1.1
f5 big-ip analytics>= 15.1.0 and < 15.1.3
f5 big-ip analytics>= 16.0.0 and < 16.0.1.1
Show all 28 affected productsf5 big-ip application acceleration manager>= 15.1.0 and < 15.1.3
f5 big-ip application acceleration manager>= 16.0.0 and < 16.0.1.1
f5 big-ip application security manager>= 15.1.0 and < 15.1.3
f5 big-ip application security manager>= 16.0.0 and < 16.0.1.1
f5 big-ip ddos hybrid defender>= 15.1.0 and < 15.1.3
f5 big-ip ddos hybrid defender>= 16.0.0 and < 16.0.1.1
f5 big-ip domain name system>= 15.1.0 and < 15.1.3
f5 big-ip domain name system>= 16.0.0 and < 16.0.1.1
f5 big-ip fraud protection service>= 15.1.0 and < 15.1.3
f5 big-ip fraud protection service>= 16.0.0 and < 16.0.1.1
f5 big-ip global traffic manager>= 15.1.0 and < 15.1.3
f5 big-ip global traffic manager>= 16.0.0 and < 16.0.1.1
f5 big-ip link controller>= 15.1.0 and < 15.1.3
f5 big-ip link controller>= 16.0.0 and < 16.0.1.1
f5 big-ip local traffic manager>= 15.1.0 and < 15.1.3
f5 big-ip local traffic manager>= 16.0.0 and < 16.0.1.1
f5 big-ip policy enforcement manager>= 15.1.0 and < 15.1.3
f5 big-ip policy enforcement manager>= 16.0.0 and < 16.0.1.1
f5 big-ip ssl orchestrator>= 15.1.0 and < 15.1.3
f5 big-ip ssl orchestrator>= 16.0.0 and < 16.0.1.1

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Scoring & Timeline

7.5

HIGH · CVSS v3.1 · f5sirt@f5.com

View on NVD

Attack Vector

Network Adjacent Local Physical

Attack Complexity

Low High

Privileges Required

None Low High

User Interaction

None Required

Scope

Unchanged Changed

Confidentiality

None Low High

Integrity

None Low High

Availability

None Low High

Published to NVD10 May 2021 · 03:15 PM

CVSS VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

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References & Sources

Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.

https://support.f5.com/csp/article/K90603426Vendor Advisory

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