Title: ====== Paypal BugBounty #2 - Persistent Listing Web Vulnerability Date: ===== 2012-11-26 References: =========== http://www.vulnerability-lab.com/get_content.php?id=634 VL-ID: ===== 634 Common Vulnerability Scoring System: ==================================== 4 Introduction: ============= 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. On October 3, 2002, PayPal became a wholly owned subsidiary of eBay. Its corporate headquarters are in San Jose, California, United States at eBay s North First Street satellite office campus. The company also has significant operations in Omaha, Nebraska, Scottsdale, Arizona, and Austin, Texas, in the United States, Chennai, Dublin, Kleinmachnow (near Berlin) and Tel Aviv. As of July 2007, across Europe, PayPal also operates as a Luxembourg-based bank. On March 17, 2010, PayPal entered into an agreement with China UnionPay (CUP), China s bankcard association, to allow Chinese consumers to use PayPal to shop online.PayPal is planning to expand its workforce in Asia to 2,000 by the end of the year 2010. Between December 4–9, 2010, PayPal services were attacked in a series of denial-of-service attacks organized by Anonymous in retaliation for PayPal s decision to freeze the account of WikiLeaks citing terms of use violations over the publication of leaked US diplomatic cables. (Copy of the Homepage: www.paypal.com) [http://en.wikipedia.org/wiki/PayPal] Abstract: ========= The Vulnerability Laboratory Research Team discovered a Web Vulnerability in the official Paypal ecommerce website application. Report-Timeline: ================ 2012-06-30: Researcher Notification & Coordination 2012-06-30: Vendor Notification 2012-07-02: Vendor Response/Feedback 2012-10-29: Vendor Fix/Patch by PayPal Inc 2012-11-27: Public or Non-Public Disclosure Status: ======== Published Affected Product(s): ==================== PayPal Inc Payment System - Core Application 2012 Q3-4 Exploitation-Technique: ======================= Remote Severity: ========= High Details: ======== A persistent input validation vulnerability is detected in the official Paypal ecommerce website content management system. The bugs allow remote attackers to implement/inject malicious script code on the application side (persistent). The persistent vulnerability is located in the Artikel pro Seite listing module with the bound vulnerable filterVal1 parameter. Remote exploitation requires low user inter action or privileged application user account for local exploitation. Successful exploitation of the vulnerability can lead to session hijacking (admin), account steal via persistent web attack or stable (persistent) context manipulation. Vulnerable Module(s): [+] Geld Anfordern > Artikel pro Seite (Listing) > Rechnungen verwalten Vulnerable Parameter(s): [+] filterVal1 - Item Index (Listing) Proof of Concept: ================= The persistent vulnerability can be exploited by remote attackers & local privileged user accounts with low required user inter action. For demonstration or reproduce ... Review: [ALL Listing] (index) Rechnungen Verwalten - Geld Anfordern > Artikel pro Seite (Listing) > filterVal1 var currencyVals = ["EUR", "AUD", "BRL", "GBP", "DKK", "HKD", "ILS", "JPY", "CAD", "MXN", "TWD", "NZD", "NOK", "PHP", "PLN", "SEK", "CHF", "SGD", "THB", "CZK", "HUF", "USD", ""]; var txt1 = "zwischen"; var txt2 = " und "; var txtLabel = "Wert 2"; var advFilter = "email"; var dateFilter = "invoice_date"; var filterVal1 = "<[PERSISTENT INJECTED SCRIPT CODE!] ;">