CVE-2021-24295Network attack vector

Database disclosure via unprepared User-Agent log query

Published May 17, 2021 · Updated Aug 3, 2024

Blind SQL injection in CleanTalk Spam protection before 5.153.4 allows remote attackers to read WordPress database data via HTTP requests. The update_log function in lib/Cleantalk/ApbctWP/Firewall/SFW.php interpolates the sanitized User-Agent into an INSERT statement without a prepared parameter. An unauthenticated visitor must first obtain ct_sfw_pass_key, then preserve a forged ct_sfw_passed cookie; timed guesses disclose emails, password hashes, and other database content.

CVSS severity7.5
High
EPSS probability4.69%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Blind SQL injection in CleanTalk Spam protection before 5.153.4 allows remote attackers to read WordPress database data via HTTP requests. The update_log function in lib/Cleantalk/ApbctWP/Firewall/SFW.php interpolates the sanitized User-Agent into an INSERT statement without a prepared parameter. An unauthenticated visitor must first obtain ct_sfw_pass_key, then preserve a forged ct_sfw_passed cookie; timed guesses disclose emails, password hashes, and other database content.

The record

CVE
CVE-2021-24295
Published
May 17, 2021
Updated
Aug 3, 2024
Vendor
CleanTalk
Product
Spam protection, Honeypot, Anti-Spam by CleanTalk
Classifications
CWE-89, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 17, 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=5.153.4 <5.153.4

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

CleanTalk · Spam protection, Honeypot, Anti-Spam by CleanTalkversion=5.153.4 <5.153.4

Published CVSS scores

5.0NIST NVDAV:N/AC:L/Au:N/C:P/I:N/A:N
7.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

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-89Improper Neutralization of Special Elements used in an SQL Command ('SQL Injection')
T1190Exploit Public-Facing Application

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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