CVE-2021-22982Network attack vector

Service interruption via malformed big3d payload parsing

Published Feb 12, 2021 · Updated Aug 3, 2024

A big3d buffer overflow in F5 BIG-IP DNS 13.1.x before 13.1.0.4 and all 12.1.x and 11.6.x allows remote authenticated users to interrupt service. The big3d daemon insecurely parses certain attacker-supplied payloads and overruns a memory buffer; F5 has not disclosed the affected parser or field. High-privilege network access is required, and the published record classifies the consequence as denial of service without further exploit detail.

CVSS severity7.2
High
EPSS probability1.03%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

A big3d buffer overflow in F5 BIG-IP DNS 13.1.x before 13.1.0.4 and all 12.1.x and 11.6.x allows remote authenticated users to interrupt service. The big3d daemon insecurely parses certain attacker-supplied payloads and overruns a memory buffer; F5 has not disclosed the affected parser or field. High-privilege network access is required, and the published record classifies the consequence as denial of service without further exploit detail.

The record

CVE
CVE-2021-22982
Published
Feb 12, 2021
Updated
Aug 3, 2024
Vendor
F5 Networks
Product
BIG-IP DNS
Classifications
CWE-120, T1499.004
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. Feb 12, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

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

  1. Affected versionversion=13.1.x before 13.1.0.4, and all versions of 12.1.x and 11.6.x

What conditions does exploitation require?

Attack vectornetwork
Required privilegesadmin

What is affected?

F5 Networks · BIG-IP DNSversion=13.1.x before 13.1.0.4, and all versions of 12.1.x and 11.6.x

Published CVSS scores

6.5NIST NVDAV:N/AC:L/Au:S/C:P/I:P/A:P
7.2NIST NVDCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/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
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-120Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')
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

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Your stack

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