CVE-2021-24371

RSVPMaker <= 8.7.2 - Server-Side Request Forgery

2021-06-29 00:00

Strategic Overview

Status: Patched in 8.7.4
Affected Plugin: RSVPMaker
Affected Version: < 8.7.3
CVSS: 2.7Low
Weakness type: CWE-918 · Server-Side Request Forgery (SSRF)
CVE: CVE-2021-24371

At a glance

CVE-2021-24371 is a low-severity Server-Side Request Forgery (SSRF) vulnerability in the RSVPMaker WordPress plugin, affecting versions < 8.7.3. It carries a CVSS score of 2.7 (reachable over the network; low attack complexity). The issue is fixed in version 8.7.4; sites on affected versions should update now. Disclosed June 2021, reported by Shreya Pohekar.

Vulnerability Overview

The Import feature of the RSVPMaker WordPress plugin before 8.7.4 (/wp-admin/tools.php?page=rsvpmaker_export_screen) takes an URL input and calls curl on it, without first validating it to ensure it's a remote one. As a result, a high privilege user could use that feature to scan the internal network via a SSRF attack.

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 interaction from a victim user.

CWE-918: Server-Side Request Forgery (SSRF)

Reaching this weakness in RSVPMaker < 8.7.3 takes a caller who can reach the endpoint. Server-side request forgery means the application fetches a URL supplied by the caller, turning the server into a proxy for requests the attacker could not make directly.

The request originates from inside the hosting network, which is how these flaws reach cloud metadata endpoints, internal admin panels and services that trust local traffic. For RSVPMaker the fix is 8.7.4: builds < 8.7.3 are affected, anything from 8.7.4 onward is not.

Remediation

Update to version 8.7.4, or a newer patched version

How does WordSec protect against this?

The attempt arrives as an ordinary request to RSVPMaker: WordSec's web application firewall inspects request payloads before WordPress loads them. None of that substitutes for the fix: RSVPMaker 8.7.4 closes this, and updating the plugin is the step that ends it.

Firewall
Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2021-24371 https://www.wordfence.com/threat-intel/vulnerabilities/id/027fa70f-8777-4a0b-b2aa-18bcdcd99cbf https://nvd.nist.gov/vuln/detail/CVE-2021-24371

Related records

Other vulnerabilities in RSVPMaker

CVSS Vector

2.7

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

Base

Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredHigh
User InteractionNone
ScopeUnchanged
ConfidentialityLow
IntegrityNone
AvailabilityNone

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