CVE-2019-16523

Events Manager <= 5.9.5 - Authenticated Stored Cross-Site Scripting

2019-10-16 00:00

Strategic Overview

Status: Patched in 5.9.6
Affected Plugin: Events Manager – Calendar, Bookings, Tickets, and more!
Affected Version: <= 5.9.5
CVSS: 6.4Medium
Weakness type: CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CVE: CVE-2019-16523

View all Events Manager – Calendar, Bookings, Tickets, and more! vulnerabilities

At a glance

CVE-2019-16523 is a medium-severity Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in the Events Manager WordPress plugin, affecting versions <= 5.9.5. It carries a CVSS score of 6.4 (reachable over the network; low attack complexity). Exploitation requires an authenticated account. The issue is fixed in version 5.9.6; sites on affected versions should update now. Disclosed October 2019, reported by Tobias Fink.

Vulnerability Overview

The events-manager plugin through 5.9.5 for WordPress (aka Events Manager) is susceptible to Stored XSS due to improper encoding and insertion of data provided to the attribute map_style of shortcodes (locations_map and events_map) provided by the plugin.

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

Reaching this weakness in Events Manager <= 5.9.5 takes any authenticated account. 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 Events Manager the fix is 5.9.6: builds <= 5.9.5 are affected, anything from 5.9.6 onward is not.

Remediation

Update to version 5.9.6, or a newer patched version

How does WordSec protect against this?

The attempt arrives as an ordinary request to Events Manager: WordSec's web application firewall inspects request payloads before WordPress loads them. None of that substitutes for the fix: Events Manager 5.9.6 closes this, and updating the plugin is the step that ends it.

Firewall
Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2019-16523 https://www.wordfence.com/threat-intel/vulnerabilities/id/249acca6-49b4-4ddf-af75-31f68921fc19 https://nvd.nist.gov/vuln/detail/CVE-2019-16523

Related records

Same weakness class

Other vulnerabilities in Events Manager – Calendar, Bookings, Tickets, and more!

CVSS Vector

6.4

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

Base

Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredLow
User InteractionNone
ScopeChanged
ConfidentialityLow
IntegrityLow
AvailabilityNone

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