CVE-2021-22993Network attack vector

Browser script execution via unsafe DOM update

Published Mar 31, 2021 · Updated Aug 3, 2024

DOM-based XSS in BIG-IP Advanced WAF and ASM releases allows remote attackers to execute script through the DoS Profile properties page. Client-side page logic writes attacker-controlled data into the document DOM without neutralizing executable markup; F5 has not disclosed the exact source or sink. Exploitation requires a user to open crafted content that reaches the affected page, after which the script runs in that user's browser context.

CVSS severity8.8
High
EPSS probability0.92%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

DOM-based XSS in BIG-IP Advanced WAF and ASM releases allows remote attackers to execute script through the DoS Profile properties page. Client-side page logic writes attacker-controlled data into the document DOM without neutralizing executable markup; F5 has not disclosed the exact source or sink. Exploitation requires a user to open crafted content that reaches the affected page, after which the script runs in that user's browser context.

The record

CVE
CVE-2021-22993
Published
Mar 31, 2021
Updated
Aug 3, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-79, T1189
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 31, 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?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

6.8NIST NVDAV:N/AC:M/Au:N/C:P/I:P/A:P
8.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/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
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1189Drive-by Compromise

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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