Lots of big changes to the way PayPal connects to your websites, so please ensure your settings are all up to date. Taken from the PayPal website:
Beginning in early 2016, PayPal will introduce a number of security-related product updates.
These updates are part of an industry-wide initiative to improve security standards. Some of these updates, like the TLS upgrade, are mandated by the PCI Security Council and are required by every website that transmits or processes cardholder data.
Merchants and developers may have to update their integrations in order to be in compliance and ensure that their applications continue to function as expected.
For PayPal customers, these updates include:
- TLS 1.2 upgrade (support for TLS 1.0 will be retired)
- IP Address Update for PayPal SFTP
- IPN Verification Postback to HTTPS (HTTP will no longer be supported)
- Merchant API Credential Upgrade (to SHA-256 2048-bit credentials)
- SSL Certificate Upgrade
- PayPal SDK Updates
TLS 1.2 Upgrade
The most secure protocol for sharing information on the web today is Transport Layer Security (TLS) version 1.2. PayPal is enabling support for TLS 1.2 for all secure connections and in 2016 will start requiring its use. You will need to verify that your environment supports TLS 1.2 and if necessary make appropriate updates. PayPal is updating its services to require TLS v1.2 for all HTTPS connections in June of 2017. After that time, all TLS v1.0 and TLS v1.1 API connections will be refused.
IP Address Update for PayPal SFTP
If your integration is set-up to systematically exchange files with PayPal’s Secure FTP Reporting / Batch Servers, please note that the IP addresses for these servers are changing. If your integration is hardcoded to the current IP addresses, you will need to upgrade accordingly. You must act by April 14, 2016.
IPN Verification Postback to HTTPS
If you are using PayPal’s Instant Payment Notification (IPN) service, you will need to ensure that HTTPS is used when posting the message back to PayPal for verification. After June of 2017 HTTP postbacks will no longer be supported.
Merchant API Credential Upgrade
The certificates issued by PayPal as API Credentials for use with the Classic API are being upgraded to SHA-256 signed 2048-bit certificates. If you currently connect to PayPal using Certificate API Credentials, you will need to have a new certificate issued and start using it for all API requests. Depending on when your certificate expires, you will have to upgrade between Jan 31, 2016 and Jan 1, 2018.
SSL Certificate Upgrade
PayPal is in the process of upgrading the SSL certificates used to secure our web sites and API endpoints. These new certificates will be signed using the SHA-256 algorithm and VeriSign’s 2048-bit G5 Root Certificate. You will need to ensure that your environment supports the use of the SHA-256 signing algorithm and discontinue the use of SSL connections that rely on the VeriSign G2 Root Certificate. This action must be taken by June 17, 2016 in order to avoid any disruption of service.
PayPal SDK Updates
For developers using one of PayPal’s SDK libraries, depending on the runtime environment and version your application uses, a code change or SDK update may be required in order to enable TLS v1.2. Java 6 u115 b32, Java 7 or Java 8 (preferred) and Android 4.x environments require TLS v1.2 to be enabled in order to maintain functionality.
If you’re using one of PayPal’s REST SDKs, the best practice is to stay up to date with the latest SDK version and latest versions of the code libraries required by the PayPal SDK. PayPal provides server and client SDKs for Java, .Net, PHP, Python, Ruby, Node.js, Android, and iOS. Detailed test instructions can also be found at https://github.com/paypal/TLS-update.
Developers should reference the 2016-2017 Merchant Security Roadmap microsite for all the details and up-to-date information regarding these security changes. You can also visit the PayPal Developer site for more information on PayPal security guidelines and best practices.