CVE-2021-3172Public exploitNetwork attack vector

Authenticated service interruption via poll-vote replay

Published Feb 17, 2023 · Updated Mar 19, 2025

Denial of service in PHP-Fusion 9.03.90 allows remote authenticated users to interrupt service by replaying poll-vote requests. The DisplayPoll form in infusions/member_poll_panel/poll_classes.php accepts repeated submissions because it does not limit each form token to one use. An account with access to the polling feature is required; high-volume replays inflate poll results and interrupt the application service.

CVSS severity8.1
High
EPSS probability0.65%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Denial of service in PHP-Fusion 9.03.90 allows remote authenticated users to interrupt service by replaying poll-vote requests. The DisplayPoll form in infusions/member_poll_panel/poll_classes.php accepts repeated submissions because it does not limit each form token to one use. An account with access to the polling feature is required; high-volume replays inflate poll results and interrupt the application service.

The record

CVE
CVE-2021-3172
Published
Feb 17, 2023
Updated
Mar 19, 2025
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-732, T1499
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Feb 17, 2023CVE publishedPublication date reported by the CVE source.
  2. Mar 19, 2025Record 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 privilegesauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

8.1CISA-ADPCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/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.

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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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-732Incorrect Permission Assignment for Critical Resource
T1499Endpoint Denial of Service

Public exploit references

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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