CVE-2021-24863

WP Block and Stop Bad Bots Crawlers and Spiders and Anti Spam Protection Plugin StopBadBots < 6.67 - Unauthenticated SQL Injection

2021-11-15 00:00
ZhongFu Su

Strategic Overview

Status
Patched in 6.67
Affected Plugin
Block Bad Bots and Stop Bad Bots Crawlers and Spiders and Anti Spam Protection
Affected Version
< 6.67
CVSS
9.8Critical
Weakness type
CWE-89 · Improper Neutralization of Special Elements used in an SQL Command ('SQL Injection')
CVE
CVE-2021-24863
View all Block Bad Bots and Stop Bad Bots Crawlers and Spiders and Anti Spam Protection vulnerabilities

At a glance

CVE-2021-24863 is a critical-severity Improper Neutralization of Special Elements used in an SQL Command ('SQL Injection') vulnerability in the Block Bad Bots and Stop Bad Bots Crawlers and Spiders and Anti Spam Protection WordPress plugin, affecting versions < 6.67. It carries a CVSS score of 9.8 (reachable over the network; low attack complexity; high confidentiality, integrity, availability impact). Exploitation requires no authentication. The issue is fixed in version 6.67; sites on affected versions should update now. Disclosed November 2021, reported by ZhongFu Su.

Vulnerability Overview

The WP Block and Stop Bad Bots Crawlers and Spiders and Anti Spam Protection Plugin StopBadBots WordPress plugin before 6.67 does not sanitise and escape the User Agent before using it in a SQL statement to save it, leading to a SQL injection

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, integrity, availability — full site compromise territory.

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

Reaching this weakness in Block Bad Bots and Stop Bad Bots Crawlers and Spiders and Anti Spam Protection < 6.67 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 Block Bad Bots and Stop Bad Bots Crawlers and Spiders and Anti Spam Protection the fix is 6.67: builds < 6.67 are affected, anything from 6.67 onward is not.

Remediation

Update to version 6.67, 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: Block Bad Bots and Stop Bad Bots Crawlers and Spiders and Anti Spam Protection 6.67 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-2021-24863https://www.wordfence.com/threat-intel/vulnerabilities/id/e1634f86-21c0-4b9a-b521-c6b9986f91fchttps://nvd.nist.gov/vuln/detail/CVE-2021-24863

Related records

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