CVE-2017-18593

UpdraftPlus <= 1.13.4 - Stored Cross-Site Scripting

2017-08-08 00:00

Strategic Overview

Status: Patched in 1.13.5
Affected Plugin: UpdraftPlus: WP Backup & Migration Plugin
Affected Version: <= 1.13.4
CVSS: 5.4Medium
Weakness type: CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CVE: CVE-2017-18593

View all UpdraftPlus: WP Backup & Migration Plugin vulnerabilities

At a glance

CVE-2017-18593 is a medium-severity Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in the UpdraftPlus WordPress plugin, affecting versions <= 1.13.4. It carries a CVSS score of 5.4 (reachable over the network). Exploitation requires no authentication. The issue is fixed in version 1.13.5; sites on affected versions should update now. Disclosed August 2017.

Vulnerability Overview

The updraftplus plugin before 1.13.5 for WordPress has XSS in rare cases where an attacker controls a string logged to a log file.

Technical Analysis

The vector marks this flaw as remotely reachable over the network, and no privileges on the target site, and no interaction from a victim user.

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

Reaching this weakness in UpdraftPlus <= 1.13.4 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 UpdraftPlus the fix is 1.13.5: builds <= 1.13.4 are affected, anything from 1.13.5 onward is not.

Remediation

Update to version 1.13.5, or a newer patched version

How does WordSec protect against this?

The attempt arrives as an ordinary request to UpdraftPlus: WordSec's web application firewall inspects request payloads before WordPress loads them. None of that substitutes for the fix: UpdraftPlus 1.13.5 closes this, and updating the plugin is the step that ends it.

Firewall
Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2017-18593 https://www.wordfence.com/threat-intel/vulnerabilities/id/71b3bec2-3fb2-4b0a-aa6d-5c761d0796e2 https://nvd.nist.gov/vuln/detail/CVE-2017-18593

Related records

Same weakness class

Other vulnerabilities in UpdraftPlus: WP Backup & Migration Plugin

CVSS Vector

5.4

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

Base

Attack VectorNetwork
Attack ComplexityHigh
Privileges RequiredNone
User InteractionNone
ScopeChanged
ConfidentialityLow
IntegrityLow
AvailabilityNone

This record contains material that is subject to copyright

CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE®). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy.

https://www.cve.org/Legal/TermsOfUse

Defiant hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute this software vulnerability information. Any copy of the software vulnerability information you make for such purposes is authorized provided that you include a hyperlink to this vulnerability record and reproduce Defiant's copyright designation and this license in any such copy.

https://www.wordfence.com/wordfence-intelligence-terms-and-conditions/