2.6 Low
CVSS2
Attack Vector
NETWORK
Attack Complexity
HIGH
Authentication
NONE
Confidentiality Impact
NONE
Integrity Impact
PARTIAL
Availability Impact
NONE
AV:N/AC:H/Au:N/C:N/I:P/A:N
4.7 Medium
CVSS3
Attack Vector
NETWORK
Attack Complexity
HIGH
Privileges Required
NONE
User Interaction
REQUIRED
Scope
CHANGED
Confidentiality Impact
LOW
Integrity Impact
LOW
Availability Impact
NONE
CVSS:3.0/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:L/A:N
4.8 Medium
AI Score
Confidence
High
0.001 Low
EPSS
Percentile
45.9%
# Exploit Title: Liferay Portal < 7.1 CE GA4 / SimpleCaptcha API XSS
# Date: 04/06/2019
# Exploit Author: Valerio Brussani (@val_brux)
# Website: www.valbrux.it
# Vendor Homepage: https://www.liferay.com/
# Software Link: https://www.liferay.com/it/downloads-community
# Version: < 7.1 CE GA4
# Tested on: Liferay Portal 7.1 CE GA3
# CVE: CVE-2019-6588
# Reference1: https://dev.liferay.com/web/community-security-team/known-vulnerabilities/liferay-portal-71/-/asset_publisher/7v4O7y85hZMo/content/cst-7130-multiple-xss-vulnerabilities-in-7-1-ce-ga3
# Reference2: https://www.valbrux.it/blog/2019/06/04/cve-2019-6588-liferay-portal-7-1-ce-ga4-simplecaptcha-api-xss/
Introduction
In Liferay Portal before 7.1 CE GA4, an XSS vulnerability exists in the SimpleCaptcha API when custom code passes unsanitized input
into the “url” parameter of the JSP taglib call <liferay-ui:captcha url=”<%= url %>” /> or <liferay-captcha:captcha url=”<%= url %>” />.
A customized Liferay portlet which directly calls the Simple Captcha API without sanitizing the input could be susceptible to this vulnerability.
Poc
In a sample scenario of custom code calling the <liferay-ui:captcha url=”<%= url %>” /> JSP taglib, appending a payload like the following to the body parameters of a customized form:
&xxxx%22%3e%3cscript%3ealert(1)</script>
The script is reflected in the src attribute of the <img> tag, responsible of fetching the next available captcha:
<img alt=”xxx” class=”xxxx” src=”xxxxxx“><script>alert(1)</script>=” />
2.6 Low
CVSS2
Attack Vector
NETWORK
Attack Complexity
HIGH
Authentication
NONE
Confidentiality Impact
NONE
Integrity Impact
PARTIAL
Availability Impact
NONE
AV:N/AC:H/Au:N/C:N/I:P/A:N
4.7 Medium
CVSS3
Attack Vector
NETWORK
Attack Complexity
HIGH
Privileges Required
NONE
User Interaction
REQUIRED
Scope
CHANGED
Confidentiality Impact
LOW
Integrity Impact
LOW
Availability Impact
NONE
CVSS:3.0/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:L/A:N
4.8 Medium
AI Score
Confidence
High
0.001 Low
EPSS
Percentile
45.9%