CVE-2021-24809

BP Better Messages <= 1.9.9.37 - Cross-Site Request Forgery

2021-10-04 00:00

Strategic Overview

Status: Patched in 1.9.9.41
Affected Plugin: Better Messages – Chat Rooms, Group Chat, Private Messages & AI Chat Bots
Affected Version: < 1.9.9.41
CVSS: 8.8High
Weakness type: CWE-352 · Cross-Site Request Forgery (CSRF)
CVE: CVE-2021-24809

View all Better Messages – Chat Rooms, Group Chat, Private Messages & AI Chat Bots vulnerabilities

At a glance

CVE-2021-24809 is a high-severity Cross-Site Request Forgery (CSRF) vulnerability in the Better Messages WordPress plugin, affecting versions < 1.9.9.41. It carries a CVSS score of 8.8 (reachable over the network; low attack complexity; high confidentiality, integrity, availability impact). Exploitation requires no authentication. The issue is fixed in version 1.9.9.41; sites on affected versions should update now. Disclosed October 2021, reported by Brandon James Roldan (tomorrowisnew).

Vulnerability Overview

The BP Better Messages WordPress plugin before 1.9.9.41 does not check for CSRF in multiple of its AJAX actions: bp_better_messages_leave_chat, bp_better_messages_join_chat, bp_messages_leave_thread, bp_messages_mute_thread, bp_messages_unmute_thread, bp_better_messages_add_user_to_thread, bp_better_messages_exclude_user_from_thread. This could allow attackers to make logged in users do unwanted actions

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. A successful exploit has high impact on confidentiality, integrity, availability — full site compromise territory.

CWE-352: Cross-Site Request Forgery (CSRF)

Reaching this weakness in Better Messages < 1.9.9.41 takes a caller who can reach the endpoint. Cross-site request forgery abuses the fact that browsers attach a victim's cookies to any request, so a state-changing action that only checks who you are, not whether you meant to act, can be triggered from another site.

An attacker who gets a logged-in user to load a crafted page can perform that action as them, with the impact scaling to whatever the victim's role is allowed to do. For Better Messages the fix is 1.9.9.41: builds < 1.9.9.41 are affected, anything from 1.9.9.41 onward is not.

Remediation

Update to version 1.9.9.41, or a newer patched version

How does WordSec protect against this?

The attempt arrives as an ordinary request to Better Messages: WordSec's web application firewall inspects request payloads before WordPress loads them. None of that substitutes for the fix: Better Messages 1.9.9.41 closes this, and updating the plugin is the step that ends it.

Firewall
Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2021-24809 https://www.wordfence.com/threat-intel/vulnerabilities/id/eb89a16c-fae0-4d36-85aa-79beab753cba https://nvd.nist.gov/vuln/detail/CVE-2021-24809

Related records

Same weakness class

Other vulnerabilities in Better Messages – Chat Rooms, Group Chat, Private Messages & AI Chat Bots

CVSS Vector

8.8

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

Base

Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredNone
User InteractionRequired
ScopeUnchanged
ConfidentialityHigh
IntegrityHigh
AvailabilityHigh

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