illustration of ProtonCalendar security model

The ProtonCalendar security model

December 5th, 2019 in Security

This article documents ProtonCalendar’s security model and illustrates how our product protects calendar-related sensitive data. We examine the advantages and limitations of our approach. This document is somewhat technical, discussing how encryption protects the different layers of data. Still, it is meant to be accessible to a general audience and attempts to explain how ProtonCalendar …

illustration of EU e-evidence law

Everything wrong with the EU’s proposals for gathering electronic evidence

November 29th, 2019 in Articles & News

The European Commission recently submitted proposals for new rules governing how e-evidence is gathered by law enforcement agencies. E-evidence would include things like emails, messages, and other data related to a possible crime or investigation. It is certainly important that law enforcement can gather evidence and conduct thorough criminal investigations. However, just as there are …

illustration of ProtonMail Black Friday sale

Our Black Friday sale has started! Get up to 50% off ProtonMail and ProtonVPN

November 26th, 2019 in Articles & News

Update Nov. 30, 2019: Because ProtonMail only offers discounts once per year, we have decided to extend our Black Friday promotion until 11:59 PM on Dec. 8, 2019, San Francisco time. (That’s 2:59 AM Dec. 9 in New York and 8:59 AM Dec. 9 in Geneva, Switzerland.) This extension will give anyone who wasn’t able …

illustration of ProtonMail iOS client security

ProtonMail iOS client security

October 30th, 2019 in Security

This post documents ProtonMail’s iOS security model and illustrates how our application protects sensitive data on client iOS devices. The advantages and limitations of this approach are discussed, and the source code can be viewed here. You can also ProtonMail’s iOS open source announcement. You can also read our previously published ProtonMail threat model, which …

Alternative app stores for ProtonMail’s Android app

September 5th, 2019 in Articles & News

UPDATE Sept 8th, 2019 – This blog post has been reported in some mainstream media as ProtonMail is considering to “partner with Huawei”. ProtonMail is not partnering with Huawei. We are simply considering allowing ProtonMail to be used by people with Huawei devices. That is very different. A better explanation can be found here. At …

Update on the question of voluntary real-time surveillance

May 29th, 2019 in Privacy

Updated on September 12, 2019. As the blog post referenced by this post has been removed, this post no longer serves a purpose so we have removed it. To remove any doubt, we confirm that ProtonMail has not and does not engage in voluntary real-time surveillance on behalf of law enforcement. We also confirm that …

ProtonMail SSL certificates and DarkMatter

February 25th, 2019 in Security

UPDATE Nov. 4, 2019: We are now using SwissSign AG as the certificate authority to issue our SSL/TLS certificate. Learn more about how to verify’s SSL certificate. Earlier today, the Electronic Frontier Foundation reported that the Emirati cybersecurity firm DarkMatter had applied to become a top-level certificate authority. Certificate authorities (CA) issue digital certificates …

A cybersecurity guide for small businesses

February 7th, 2019 in Security

The Internet allows businesses of any size to work and reach markets around the world. Unfortunately, this potential for increased productivity and profitability is tempered by the security risks that the Internet presents. The fact is that cybersecurity must be a part of any business plan going forward. This is meant to be a quick …

Response to analysis of ProtonMail’s cryptographic architecture

January 20th, 2019 in Security

Recently, a self-published paper that was not peer reviewed claimed weaknesses in ProtonMail’s cryptographic architecture. The document is rather dense, and the casual reader is unlikely to be able to understand much beyond the alarming conclusion that there are allegedly “serious shortcomings in ProtonMail’s cryptographic architecture.” Below, we analyze these allegations one by one, so …


January 17th, 2019 in Articles & News

今天,我们为14亿中国人带来了本地化支持。这是我们为所有人带来互联网隐私和安全的使命中非常重要的一步。 Today, we’re making ProtonMail more accessible for 1.4 billion native Chinese speakers, a major step forward in our mission to bring Internet privacy and security to all. 从现在开始,除了已经支持的14种语言外,您还可以使用简体中文和繁体中文为ProtonMail的默认语言。要更改默认语言,只需要在mail.protonmail.com中登录帐户,选择导航条的”设置(Settings)”,然后在”语言(Language)”下拉菜单中选择您语言即可。 自去年推出的志愿者翻译项目以来,中文本地化一直是ProtonMail的首要任务。这个志愿者计划的目标是翻译ProtonMail静态页面,网页应用界面以及iOS和Android应用程序。ProtonMail已支持捷克语,荷兰语,英语,法语,德语,意大利语,日语,波兰语,葡萄牙语,罗马尼亚语,俄语,西班牙语,土耳其语和乌克兰语。 中国拥有超过7亿的互联网用户,并且在线人数超过世界上任何其他国家。中文也是使用最广泛的语言,其次是西班牙语和英语。繁体中文是香港和台湾人的主要书面文字,简体中文主要用于中国大陆和新加坡。 现在ProtonMail已经覆盖超过30亿人的母语本地化。这要归功于翻译志愿者的支持。非常感谢ProtonMail的社区对翻译工作的帮助。 我们正在积极努力带来更多语言的本地化。如果目前ProtonMail不支持您的母语,我们邀请您并希望您能加入翻译项目。访问此页面了解更多详情。 诚挚的问候, ProtonMail团队

ProtonMail Lifetime Account charity auction raises over €30,000

December 25th, 2018 in Articles & News

Our first-ever charity auction has exceeded all expectations, generating over €30,000 for three organizations dedicated to human rights and online privacy. When we launched our Lifetime Account auction earlier this month, we expected to raise around €3500-5000 from each sale. But when bidding closed today, each auction had far surpassed our target, with all three …

black friday scams

Don’t fall for Black Friday email scams

November 22nd, 2018 in Articles & News

You’ve heard the one about the Nigerian prince and the lottery windfall (we just need your bank account and social security number!). But email phishing scams are getting more sophisticated and persuasive. While they come in a variety of forms, the general goal of a phishing attack is to trick you into giving away sensitive …

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