CVE-2021-24406

wpForo Forum <= 1.9.6 - Open Redirect

2021-06-14 00:00

Strategic Overview

Status: Patched in 1.9.7
Affected Plugin: wpForo Forum
Affected Version: <= 1.9.6
CVSS: 6.1Medium
Weakness type: CWE-601 · URL Redirection to Untrusted Site ('Open Redirect')
CVE: CVE-2021-24406

At a glance

CVE-2021-24406 is a medium-severity URL Redirection to Untrusted Site ('Open Redirect') vulnerability in the wpForo Forum WordPress plugin, affecting versions <= 1.9.6. It carries a CVSS score of 6.1 (reachable over the network; low attack complexity). Exploitation requires no authentication. The issue is fixed in version 1.9.7; sites on affected versions should update now. Disclosed June 2021, reported by Hosein_vita.

Vulnerability Overview

The wpForo Forum WordPress plugin before 1.9.7 did not validate the redirect_to parameter in the login form of the forum, leading to an open redirect issue after a successful login. Such issue could allow an attacker to induce a user to use a login URL redirecting to a website under their control and being a replica of the legitimate one, asking them to re-enter their credentials (which will then in the attacker hands)

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.

CWE-601: URL Redirection to Untrusted Site ('Open Redirect')

Reaching this weakness in wpForo Forum <= 1.9.6 takes a caller who can reach the endpoint. An open redirect is a page that takes a destination from the request and sends the browser there without checking that the destination belongs to the site.

A link that starts on a trusted domain finishes on an attacker's, which is what makes phishing and consent-screen abuse credible to the person clicking it. For wpForo Forum the fix is 1.9.7: builds <= 1.9.6 are affected, anything from 1.9.7 onward is not.

Remediation

Update to version 1.9.7, or a newer patched version

How does WordSec protect against this?

The attempt arrives as an ordinary request to wpForo Forum: WordSec's web application firewall inspects request payloads before WordPress loads them. None of that substitutes for the fix: wpForo Forum 1.9.7 closes this, and updating the plugin is the step that ends it.

Firewall
Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2021-24406 https://www.wordfence.com/threat-intel/vulnerabilities/id/ebf84c6a-fd6c-4113-91ff-27c7564cabdb https://nvd.nist.gov/vuln/detail/CVE-2021-24406

Related records

Other vulnerabilities in wpForo Forum

CVSS Vector

6.1

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

Base

Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredNone
User InteractionRequired
ScopeChanged
ConfidentialityLow
IntegrityLow
AvailabilityNone

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