CVE-2020-5861Network attack vector

Service interruption via incorrect Ram Cache optimization

Published Mar 27, 2020 · Updated Aug 4, 2024

Denial of service in F5 Networks BIG-IP 12.1.0 through 12.1.5 allows remote attackers to crash TMM through affected HTTP traffic. The Ram Cache optimizer incorrectly optimizes stored response data, causing memory errors in the Traffic Management Microkernel process. The condition requires Ram Cache to process affected stored data; triggering it produces a core file and interrupts traffic handled by that TMM instance.

CVSS severity7.5
High
EPSS probability1.04%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Denial of service in F5 Networks BIG-IP 12.1.0 through 12.1.5 allows remote attackers to crash TMM through affected HTTP traffic. The Ram Cache optimizer incorrectly optimizes stored response data, causing memory errors in the Traffic Management Microkernel process. The condition requires Ram Cache to process affected stored data; triggering it produces a core file and interrupts traffic handled by that TMM instance.

The record

CVE
CVE-2020-5861
Published
Mar 27, 2020
Updated
Aug 4, 2024
Vendor
F5 Networks
Product
BIG-IP
Classifications
CWE-119, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 27, 2020CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=12.1.0-12.1.5

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

F5 Networks · BIG-IPversion=12.1.0-12.1.5

Published CVSS scores

7.5NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-119Improper Restriction of Operations within the Bounds of a Memory Buffer
T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo