CVE-2021-24295

Spam protection, AntiSpam, FireWall by CleanTalk <= 5.153.3 - Unauthenticated Blind SQL Injection

2021-03-05 00:00

Strategic Overview

Status: Patched in 5.153.4
Affected Plugin: Spam protection, Honeypot, Anti-Spam by CleanTalk
Affected Version: <= 5.153.3
CVSS: 7.5High
Weakness type: CWE-89 · Improper Neutralization of Special Elements used in an SQL Command ('SQL Injection')
CVE: CVE-2021-24295

View all Spam protection, Honeypot, Anti-Spam by CleanTalk vulnerabilities

At a glance

CVE-2021-24295 is a high-severity Improper Neutralization of Special Elements used in an SQL Command ('SQL Injection') vulnerability in the Spam protection, Honeypot, Anti-Spam by CleanTalk WordPress plugin, affecting versions <= 5.153.3. It carries a CVSS score of 7.5 (reachable over the network; low attack complexity; high confidentiality impact). Exploitation requires no authentication. The issue is fixed in version 5.153.4; sites on affected versions should update now. Disclosed March 2021, reported by Ram.

Vulnerability Overview

It was possible to exploit an Unauthenticated Time-Based Blind SQL Injection vulnerability in the Spam protection, AntiSpam, FireWall by CleanTalk WordPress Plugin before 5.153.4. The update_log function in lib/Cleantalk/ApbctWP/Firewall/SFW.php included a vulnerable query that could be injected via the User-Agent Header by manipulating the cookies set by the Spam protection, AntiSpam, FireWall by CleanTalk WordPress plugin before 5.153.4, sending an initial request to obtain a ct_sfw_pass_key cookie and then manually setting a separate ct_sfw_passed cookie and disallowing it from being reset.

Technical Analysis

The vector marks this flaw as remotely reachable over the network, with low attack complexity — no special timing or configuration is needed, and no privileges on the target site, and no interaction from a victim user. A successful exploit has high impact on confidentiality.

CWE-89: Improper Neutralization of Special Elements used in an SQL Command ('SQL Injection')

Reaching this weakness in Spam protection, Honeypot, Anti-Spam by CleanTalk <= 5.153.3 takes no account at all. SQL injection happens when request data is concatenated into a query instead of being bound as a parameter, letting an attacker change the structure of the statement rather than just its values.

A working injection can read any table the database user can see, which on a WordPress install means user records, password hashes and session or API secrets stored in options. For Spam protection, Honeypot, Anti-Spam by CleanTalk the fix is 5.153.4: builds <= 5.153.3 are affected, anything from 5.153.4 onward is not.

Remediation

Update to version 5.153.4, or a newer patched version

How does WordSec protect against this?

Requests carrying this pattern arrive without a session, so nothing upstream of the firewall gets a chance to reject them: WordSec's web application firewall inspects request payloads before WordPress loads them. None of that substitutes for the fix: Spam protection, Honeypot, Anti-Spam by CleanTalk 5.153.4 closes this, and updating the plugin is the step that ends it.

Firewall
Login Security
Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2021-24295 https://www.wordfence.com/threat-intel/vulnerabilities/id/7fe50510-6736-4bcf-b62f-0b8d2cb8ff3a https://nvd.nist.gov/vuln/detail/CVE-2021-24295

Related records

Same weakness class

Other vulnerabilities in Spam protection, Honeypot, Anti-Spam by CleanTalk

CVSS Vector

7.5

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Base

Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredNone
User InteractionNone
ScopeUnchanged
ConfidentialityHigh
IntegrityNone
AvailabilityNone

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