CVE-2022-39281Public exploitNetwork attack vector

Authenticated application hang via unrestricted Ruby send

Published Oct 8, 2022 · Updated Apr 23, 2025

Improper input validation in Fat Free CRM before 0.20.1 allows remote authenticated users to hang the web application through task updates. Task update endpoints pass the user-controlled bucket parameter to Task.bucket_empty?, which invokes Ruby send without restricting the requested method to configured task buckets. A valid session and CSRF token are required; repeated requests selecting Kernel.sleep indefinitely occupy every Puma worker thread and stop request handling.

CVSS severity6.5
Medium
EPSS probability1.57%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper input validation in Fat Free CRM before 0.20.1 allows remote authenticated users to hang the web application through task updates. Task update endpoints pass the user-controlled bucket parameter to Task.bucket_empty?, which invokes Ruby send without restricting the requested method to configured task buckets. A valid session and CSRF token are required; repeated requests selecting Kernel.sleep indefinitely occupy every Puma worker thread and stop request handling.

The record

CVE
CVE-2022-39281
Published
Oct 8, 2022
Updated
Apr 23, 2025
Vendor
Fat Free CRM
Product
Fat Free CRM
Classifications
CWE-20, T1499.004
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Oct 8, 2022CVE publishedPublication date reported by the CVE source.
  2. Apr 23, 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?

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

  1. Affected versionversion=< 0.20.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Fat Free CRM · Fat Free CRMversion=< 0.20.1

Published CVSS scores

6.5GitHub, Inc.CVSS:3.1/AV:N/AC:L/PR:L/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.

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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-20Improper Input Validation
T1499.004Application or System Exploitation

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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