Document Title:
===============
PayPal (Notify) - Bypass & Persistent Web Vulnerability
References (Source):
====================
http://www.vulnerability-lab.com/get_content.php?id=1640
Video: http://www.vulnerability-lab.com/get_content.php?id=1639
Release Date:
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2018-06-22
Vulnerability Laboratory ID (VL-ID):
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1640
Common Vulnerability Scoring System:
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4.1
Vulnerability Class:
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Cross Site Scripting - Persistent
Current Estimated Price:
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1.000€ - 2.000€
Product & Service Introduction:
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PayPal is a global e-commerce business allowing payments and money transfers to be made through the Internet. Online money
transfers serve as electronic alternatives to paying with traditional paper methods, such as checks and money orders. Originally,
a PayPal account could be funded with an electronic debit from a bank account or by a credit card at the payer s choice. But some
time in 2010 or early 2011, PayPal began to require a verified bank account after the account holder exceeded a predetermined
spending limit. After that point, PayPal will attempt to take funds for a purchase from funding sources according to a specified
funding hierarchy. If you set one of the funding sources as Primary, it will default to that, within that level of the hierarchy
(for example, if your credit card ending in 4567 is set as the Primary over 1234, it will still attempt to pay money out of your
PayPal balance, before it attempts to charge your credit card). The funding hierarchy is a balance in the PayPal account; a
PayPal credit account, PayPal Extras, PayPal SmartConnect, PayPal Extras Master Card or Bill Me Later (if selected as primary
funding source) (It can bypass the Balance); a verified bank account; other funding sources, such as non-PayPal credit cards.
The recipient of a PayPal transfer can either request a check from PayPal, establish their own PayPal deposit account or request
a transfer to their bank account.
PayPal is an acquirer, performing payment processing for online vendors, auction sites, and other commercial users, for which it
charges a fee. It may also charge a fee for receiving money, proportional to the amount received. The fees depend on the currency
used, the payment option used, the country of the sender, the country of the recipient, the amount sent and the recipient s account
type. In addition, eBay purchases made by credit card through PayPal may incur extra fees if the buyer and seller use different currencies.
(Copy of the Homepage: www.paypal.com) [http://en.wikipedia.org/wiki/PayPal]
Abstract Advisory Information:
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The Vulnerability Laboratory Core Research Team discovered an application-side input validation web vulnerability in the official PayPal Inc Notify online service web-application.
Vulnerability Disclosure Timeline:
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2018-06-22: Public Disclosure (Vulnerability Laboratory - Shared Customer Research Feed)
Discovery Status:
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Published
Affected Product(s):
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Exploitation Technique:
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Remote
Severity Level:
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Medium
Authentication Type:
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No authentication (guest)
User Interaction:
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Low User Interaction
Disclosure Type:
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Bug Bounty Program
Technical Details & Description:
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An application-side input validation web vulnerability has been discovered in the official PayPal Inc Notify online service web-application.
The vulnerbaility allows remote attackers to inject malicious script codes on the application-side of the affected online service module.
The vulnerability is located in the firstname and lastname input fields of the paypal notify registration formular. Remote attackers are able
to register an account with malicious script codes as firstname and lastname to compromise the affected module. The request method to inject
is POST and the attack vector of the vulnerability is located on the application-side of the vulnerable module. The remote attacker injects a
payload as name value to execute the code in the account cancel notify email.
The security risk of the application-side web vulnerability is estimated as medium with a cvss (common vulnerability scoring system) count of 4.1.
Exploitation of the application-side validation web vulnerability requires a low privileged web-application user account and low user interaction.
Successful exploitation of the vulnerability results in session hijacking, persistent phishing attacks, persistent redirect to external sources
and persistent manipulation of affected or connected service module context.
Request Method(s):
[+] [POST]
Vulnerable Domain(s):
[+] PayPal Inc - Notify (www.paypal-notify.com)
Vulnerable Module(s):
[+] ./account/view
Vulnerable Parameter(s):
[+] firstname
[+] lastname
Affected Module(s):
[+] Notification Account Transfer Cancelled (Form Page & eMail)
Proof of Concept (PoC):
=======================
The vulnerability can be exploited by remote attacker with low privilege web-application user account and low or medium user interaction.
For security demonstration or to reproduce the vulnerability follow the provided information and steps below to continue.
Manual steps to reproduce the vulnerability ...
1. Create account with name have a code payload ( https://www.paypal-notify.com/)
First Name:
Last Name:
tested by VulnerabilityLabs
2. Go to Account Options > Transfer Account Admin https://www.paypal-notify.com/account/transfer?type=initiate and i send request to victim email and also cancel
3. When the victim will open the mail will get mail with injected code html the payload code from email: noreply@paypal.com
PoC: Exploitation
style="font-size: 16px; font-weight: bold; color: #ca802e;">Notification
Account Transfer Cancelled
[PERSISTENT INJECTED SCRIPT CODE EXECUTION VIA NAME VALUES!]tested by VulnerabilityLabs