Last Updated: July 1, 2021
1. This Twilio Security Overview (“Security Overview”) is incorporated into and made a part of (a) Twilio’s Terms of Service available at https://www.twilio.com/legal/tos; (b) the Twilio Platform Agreement; or (c) a similar written agreement between Twilio and Customer for Customer’s use of the Services (each, the “Agreement”). “Services”, “Twilio Services”, and “SendGrid Services” will each have the meaning given to it in the Data Protection Addendum available at https://www.twilio.com/legal/data-protection-addendum (“Data Protection Addendum”). Any capitalized term used but not defined in this Security Overview will have the meaning given to it in either the Agreement or the Data Protection Addendum.
2. Purpose. This Security Overview describes Twilio’s security program, security certifications, and technical and organizational security controls to protect (a) Customer Data from unauthorized use, access, disclosure, or theft and (b) the Services. In addition to this Security Overview, Twilio’s technical security documentation for the Twilio APIs is available at https://www.twilio.com/docs/api/security. As security threats shift and evolve, Twilio continues to update its security program and strategy to help protect Customer Data and the Services. As such, Twilio reserves the right to update this Security Overview from time to time; provided, however, any update will not materially reduce the overall protections set forth in this Security Overview. The then-current terms of this Security Overview are available at https://www.twilio.com/legal/security-overview. This Security Overview does not apply to any Beta Offerings or communications services provided by telecommunications providers.
3. Security Organization and Program. Twilio maintains a risk-based assessment security program. The framework for Twilio’s security program includes administrative, organizational, technical, and physical safeguards reasonably designed to protect the Services and confidentiality, integrity, and availability of Customer Data. Twilio’s security program is intended to be appropriate to the nature of the Services and the size and complexity of Twilio’s business operations. Twilio has a separate and dedicated Information Security team that manages Twilio’s security program. This team facilitates and supports independent audits and assessments performed by third parties. Twilio’s security framework is based on the ISO 27001 Information Security Management System and includes programs covering: Policies and Procedures, Asset Management, Access Management, Cryptography, Physical Security, Operations Security, Communications Security, Business Continuity Security, People Security, Product Security, Cloud and Network Infrastructure Security, Security Compliance, Third-Party Security, Vulnerability Management, and Security Monitoring and Incident Response. Security is managed at the highest levels of the company, with Twilio’s Chief Trust and Security Officer meeting with executive management regularly to discuss issues and coordinate company-wide security initiatives. Information security policies and standards are reviewed and approved by management at least annually and are made available to all Twilio employees for their reference.
4. Confidentiality. Twilio has controls in place to maintain the confidentiality of Customer Data in accordance with the Agreement. All Twilio employees and contract personnel are bound by Twilio’s internal policies regarding maintaining the confidentiality of Customer Data and are contractually obligated to comply with these obligations.
5. People Security
5.1 Employee Background Checks. Twilio performs background checks on all new employees at the time of hire in accordance with applicable local laws. Twilio currently verifies a new employee’s education and previous employment and performs reference checks. Where permitted by applicable law, Twilio may also conduct criminal, credit, immigration, and security checks depending on the nature and scope of a new employee’s role.
5.2 Employee Training. At least once (1) a year, all Twilio employees must complete a security and privacy training which covers Twilio’s security policies, security best practices, and privacy principles. Employees on a leave of absence may have additional time to complete this annual training. Twilio’s dedicated security team also performs phishing awareness campaigns and communicates emerging threats to employees. Twilio has also established an anonymous hotline for employees to report any unethical behavior where anonymous reporting is legally permitted.
6. Third Party Vendor Management
6.1 Vendor Assessment. Twilio may use third party vendors to provide the Services. Twilio carries out a security risk-based assessment of prospective vendors before working with them to validate they meet Twilio’s security requirements. Twilio periodically reviews each vendor in light of Twilio’s security and business continuity standards, including the type of access and classification of data being accessed (if any), controls necessary to protect data, and legal/regulatory requirements. Twilio ensures that Customer Data is returned and/or deleted at the end of a vendor relationship. For the avoidance of doubt, telecommunication providers are not considered subcontractors or third-party vendors of Twilio.
6.2 Vendor Agreements. Twilio enters into written agreements with all of its vendors which include confidentiality, privacy and, security obligations that provide an appropriate level of protection for Customer Data that these vendors may process.
7. Security Certifications. Twilio holds the following security-related certifications:
All Twilio Services
ISO/IEC 27017 & 27018
All Twilio Services
SOC 2 Type II
(Trust Service Principles: Security & Availability)
The following Twilio Services: Programmable Voice, Programmable Messaging, Programmable Video, and Authy
All SendGrid Services
PCI DSS Level 1
Programmable Voice portion of the Twilio Services
PCI DSS Level 4
All SendGrid Services
8. Architecture and Data Segregation
8.1 Twilio Services. The cloud communication platform for the Twilio Services is hosted by Amazon Web Services (“AWS”). The AWS data center infrastructure used in providing the Twilio Services is located in the United States. Additional information about security provided by AWS is available at https://aws.amazon.com/security and https://aws.amazon.com/whitepapers/overview-of-security-processes. Twilio’s production environment within AWS, where Customer Data and the Twilio Services are hosted, is a logically isolated Virtual Private Cloud (VPC).
8.2 SendGrid Services. For the SendGrid Services, Twilio leverages colocation data centers, provided by Zayo and Centurylink, which are located in the United States.
8.3 Services. For the Services, all network access between production hosts is restricted, using firewalls to allow only authorized services to interact in the production network. Firewalls are in use to manage network segregation between different security zones in the production and corporate environments. Firewall rules are reviewed regularly. Twilio separates Customer Data using logical identifiers which tag Customer Data with a unique customer indentifier that is assigned to Customer to clearly identify ownership. The Twilio APIs are designed and built to identify and allow access only to and from these tags. These controls prevent other customers from having access to Customer Data.
9. Physical Security. AWS data centers that host the Twilio Services and the colocation data centers provided by Zayo and Centurylink that are used for the SendGrid Services are strictly controlled both at the perimeter and at building ingress points by professional security staff utilizing video surveillance, intrusion detection systems, and other electronic means. Authorized staff must pass two-factor authentication (2FA) a minimum of two (2) times to access data center floors. All visitors and contractors are required to present identification and are signed in and continually escorted by authorized staff. These facilities are designed to withstand adverse weather and other reasonably predictable natural conditions. Each data center has redundant electrical power systems that are available twenty-four (24) hours a day, seven (7) days a week. Uninterruptible power supplies and on-site generators are available to provide back-up power in the event of an electrical failure. In addition, Twilio headquarters and office spaces have a physical security program that manages visitors, building entrances, CCTVs (closed circuit televisions), and overall office security. All employees, contractors, and visitors are required to wear identification badges.
10. Security by Design. Twilio follows security by design principles when it designs the Services. Twilio also applies the Twilio Secure Software Development Lifecycle (Secure SDLC) standard to perform numerous security-related activities for the Services across different phases of the product creation lifecycle from requirements gathering and product design all the way through product deployment. These activities include, but are not limited to, the performance of (a) internal security reviews before new Services are deployed; (b) penetration tests performed on new Services by independent third parties; and (c) threat models for new Services to detect of any potential security threats and vulnerabilities.
11. Access Controls
11.1 Provisioning Access. To minimize the risk of data exposure, Twilio follows the principles of least privilege through a team-based-access-control model when provisioning system access. Twilio personnel are authorized to access Customer Data based on their job function, role and responsibilities, and such access requires approval of the employee’s manager. Access rights to production environments are reviewed at least semi-annually. An employee’s access to Customer Data is promptly removed upon termination of their employment. In order to access the production environment, an authorized user must have a unique username and password, multi-factor authentication and be connected to Twilio’s Virtual Private Network (VPN). Before an engineer is granted access to the production environment, access must be approved by management and the engineer is required to complete internal trainings for such access including trainings on the relevant team’s systems. Twilio logs high risk actions and changes in the production environment. Twilio leverages automation to identify any deviation from internal technical standards that could indicate anomalous/unauthorized activity to raise an alert within minutes of a configuration change.
11.2 Password Controls. Twilio’s current policy for employee password management follows the NIST 800-63B guidance, and as such, our policy is to use longer passwords, with multi-factor authentication but not require special characters or frequent changes. For the SendGrid Services, password requirements include a ten (10) character minimum, with at least three (3) of the following characteristics: upper case letter, lower case letter, number, or special character. When a customer logs into its account, Twilio hashes the credentials of the user before it is stored. A customer may also require its users to add another layer of security to their account by using two-factor authentication (2FA).
12. Change Management. Twilio has a formal change management process it follows to administer changes to the production environment for the Services, including any changes to its underlying software, applications, and systems. Each change is carefully reviewed and evaluated in a test environment before being deployed into the production environment for the Services. All changes, including the evaluation of the changes in a test environment, are documented using a formal, auditable, system of record. A rigorous assessment is carried out for all high-risk changes to evaluate their impact on the overall security of the Services. Deployment approval for high-risk changes is required from the correct organizational stakeholders. Plans and procedures are also implemented in the event a deployed change needs to be rolled back to preserve the security of the Services.
13. Encryption. For the Twilio Services, (a) the databases that store Customer Data are encrypted using the Advanced Encryption Standard and (b) Customer Data is encrypted when in transit between Customer’s software application and the Services using TLS v1.2. For the SendGrid Services, Twilio provides opportunistic TLS v1.1 or higher for emails in transit between Customer’s software application and the recipient’s email server. The SendGrid Services are designed to opportunistically try outbound TLS v1.1 or higher when attempting to deliver an email to a recipient. This means that if a recipient's email server accepts an inbound TLS v1.1 or higher connection, Twilio will deliver an email over a TLS encrypted connection. If a recipient’s email server does not support TLS, Twilio will deliver an email over the default unencrypted connection. The SendGrid Services provide an optional feature, which Customer has to enable, that allows Customer to enforce TLS encryption. If Customer enables the enforced TLS feature, Twilio will only deliver an email to a recipient if the recipient’s email server accepts an inbound TLS v1.1 or higher connection.
14. Vulnerability Management. Twilio maintains controls and policies to mitigate the risk of security vulnerabilities in a measurable time frame that balances risk and the business/operational requirements. Twilio uses a third-party tool to conduct vulnerability scans regularly to assess vulnerabilities in Twilio’s cloud infrastructure and corporate systems. Critical software patches are evaluated, tested, and applied proactively. For the Twilio Services, operating system patches are applied through the regeneration of a base virtual-machine image and deployed to all nodes in the Twilio cluster over a predefined schedule. For high-risk patches, Twilio will deploy directly to existing nodes through internally developed orchestration tools.
15. Penetration Testing. Twilio performs penetration tests and engages independent third-party entities to conduct application-level penetration tests. Security threats and vulnerabilities that are detected are prioritized, triaged, and remediated promptly. Twilio maintains a Bug Bounty Program, available at https://www.bugcrowd.com/twilio, which allows independent security researchers to report security threats and vulnerabilities on an ongoing basis.
16. Security Incident Management. Twilio maintains security incident management policies and procedures in accordance with NIST SP 800-61. Twilio’s Security Incident Response Team (T-SIRT) assesses all relevant security threats and vulnerabilities and establishes appropriate remediation and mitigation actions. Twilio retains security logs for one hundred and eighty (180) days. Access to these security logs is limited to T-SIRT. Twilio utilizes third-party tools to detect, mitigate, and prevent Distributed Denial of Service (DDoS) attacks.
17. Discovery, Investigation, and Notification of a Security Incident. Twilio will promptly investigate a Security Incident upon discovery. To the extent permitted by applicable law, Twilio will notify Customer of a Security Incident in accordance with the Data Protection Addendum. Security Incident notifications will be provided to Customer via email to the email address designated by Customer in its account.
18. Resilience and Service Continuity. The Services use a variety of tools and mechanisms to achieve high availability and resiliency. For the Twilio Services, Twilio’s infrastructure spans multiple fault-independent AWS availability zones in geographic regions physically separated from one another. Twilio’s infrastructure is able to detect and route around issues experienced by hosts or even whole data centers in real time and employ orchestration tooling that has the ability to regenerate hosts, building them from the latest backup. Twilio also leverages specialized tools that monitor server performance, data, and traffic load capacity within each availability zone and colocation data center. If suboptimal server performance or overloaded capacity is detected on a server within an availability zone or colocation data center, these specialized tools increase the capacity or shift traffic to relieve any suboptimal server performance or capacity overload. Twilio is also immediately notified in the event of any suboptimal server performance or overloaded capacity.
19. Backups and Recovery. Twilio performs regular backups of Customer Data, which is hosted on AWS’s data center infrastructure. Customer Data that is backed up is retained redundantly across multiple availability zones and encrypted in transit and at rest using Advanced Encryption Standard (AES-256).