CVE-2017-18563

RSVP and Event Management Plugin <= 2.3.7 - Cross-Site Scripting

2017-06-12 00:00

Strategic Overview

Status: Patched in 2.3.8
Affected Plugin: RSVP and Event Management
Affected Version: < 2.3.8
CVSS: 6.1Medium
Weakness type: CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CVE: CVE-2017-18563

View all RSVP and Event Management vulnerabilities

At a glance

CVE-2017-18563 is a medium-severity Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in the RSVP and Event Management WordPress plugin, affecting versions < 2.3.8. 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 2.3.8; sites on affected versions should update now. Disclosed June 2017.

Vulnerability Overview

The rsvp plugin before 2.3.8 for WordPress has persistent XSS via the note field on the attendee-list screen.

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-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Reaching this weakness in RSVP and Event Management < 2.3.8 takes a caller who can reach the endpoint. Cross-site scripting happens when input from a request is written into a page without being escaped for the context it lands in, so the browser parses attacker-supplied text as markup or script.

Injected script runs with the privileges of whoever views the affected page, which is how these flaws turn into administrator session theft, silent account creation or persistent backdoors in page content. For RSVP and Event Management the fix is 2.3.8: builds < 2.3.8 are affected, anything from 2.3.8 onward is not.

Remediation

Update to version 2.3.8, or a newer patched version

How does WordSec protect against this?

The attempt arrives as an ordinary request to RSVP and Event Management: WordSec's web application firewall inspects request payloads before WordPress loads them. None of that substitutes for the fix: RSVP and Event Management 2.3.8 closes this, and updating the plugin is the step that ends it.

Firewall
Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2017-18563 https://www.wordfence.com/threat-intel/vulnerabilities/id/792d6c70-4c17-493a-bb4a-08a55e8240d3 https://nvd.nist.gov/vuln/detail/CVE-2017-18563

Related records

Same weakness class

6.1RSVP and Event Management <= 2.7.4 Cross-Site Scripting

Other vulnerabilities in RSVP and Event Management

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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