Entries Tagged "Telegram"

Page 1 of 1

Fake Signal and Telegram Apps in the Google Play Store

Google removed fake Signal and Telegram apps from its Play store.

An app with the name Signal Plus Messenger was available on Play for nine months and had been downloaded from Play roughly 100 times before Google took it down last April after being tipped off by security firm ESET. It was also available in the Samsung app store and on signalplus[.]org, a dedicated website mimicking the official Signal.org. An app calling itself FlyGram, meanwhile, was created by the same threat actor and was available through the same three channels. Google removed it from Play in 2021. Both apps remain available in the Samsung store.

Both apps were built on open source code available from Signal and Telegram. Interwoven into that code was an espionage tool tracked as BadBazaar. The Trojan has been linked to a China-aligned hacking group tracked as GREF. BadBazaar has been used previously to target Uyghurs and other Turkic ethnic minorities. The FlyGram malware was also shared in a Uyghur Telegram group, further aligning it to previous targeting by the BadBazaar malware family.

Signal Plus could monitor sent and received messages and contacts if people connected their infected device to their legitimate Signal number, as is normal when someone first installs Signal on their device. Doing so caused the malicious app to send a host of private information to the attacker, including the device IMEI number, phone number, MAC address, operator details, location data, Wi-Fi information, emails for Google accounts, contact list, and a PIN used to transfer texts in the event one was set up by the user.

This kind of thing is really scary.

Posted on September 14, 2023 at 7:05 AMView Comments

Finding the Location of Telegram Users

Security researcher Ahmed Hassan has shown that spoofing the Android’s “People Nearby” feature allows him to pinpoint the physical location of Telegram users:

Using readily available software and a rooted Android device, he’s able to spoof the location his device reports to Telegram servers. By using just three different locations and measuring the corresponding distance reported by People Nearby, he is able to pinpoint a user’s precise location.

[…]

A proof-of-concept video the researcher sent to Telegram showed how he could discern the address of a People Nearby user when he used a free GPS spoofing app to make his phone report just three different locations. He then drew a circle around each of the three locations with a radius of the distance reported by Telegram. The user’s precise location was where all three intersected.

[…]

Fixing the problem—or at least making it much harder to exploit it—wouldn’t be hard from a technical perspective. Rounding locations to the nearest mile and adding some random bits generally suffices. When the Tinder app had a similar disclosure vulnerability, developers used this kind of technique to fix it.

Posted on January 14, 2021 at 6:08 AMView Comments

The Effects of Iran's Telegram Ban

The Center for Human Rights in Iran has released a report outlining the effect’s of that country’s ban on Telegram, a secure messaging app used by about half of the country.

The ban will disrupt the most important, uncensored platform for information and communication in Iran, one that is used extensively by activists, independent and citizen journalists, dissidents and international media. It will also impact electoral politics in Iran, as centrist, reformist and other relatively moderate political groups that are allowed to participate in Iran’s elections have been heavily and successfully using Telegram to promote their candidates and electoral lists during elections. State-controlled domestic apps and media will not provide these groups with such a platform, even as they continue to do so for conservative and hardline political forces in the country, significantly aiding the latter.

From a Wired article:

Researchers found that the ban has had broad effects, hindering and chilling individual speech, forcing political campaigns to turn to state-sponsored media tools, limiting journalists and activists, curtailing international interactions, and eroding businesses that grew their infrastructure and reach off of Telegram.

It’s interesting that the analysis doesn’t really center around the security properties of Telegram, but more around its ubiquity as a messaging platform in the country.

Posted on June 22, 2018 at 12:58 PMView Comments

Russian Censorship of Telegram

Internet censors have a new strategy in their bid to block applications and websites: pressuring the large cloud providers that host them. These providers have concerns that are much broader than the targets of censorship efforts, so they have the choice of either standing up to the censors or capitulating in order to maximize their business. Today’s Internet largely reflects the dominance of a handful of companies behind the cloud services, search engines and mobile platforms that underpin the technology landscape. This new centralization radically tips the balance between those who want to censor parts of the Internet and those trying to evade censorship. When the profitable answer is for a software giant to acquiesce to censors’ demands, how long can Internet freedom last?

The recent battle between the Russian government and the Telegram messaging app illustrates one way this might play out. Russia has been trying to block Telegram since April, when a Moscow court banned it after the company refused to give Russian authorities access to user messages. Telegram, which is widely used in Russia, works on both iPhone and Android, and there are Windows and Mac desktop versions available. The app offers optional end-to-end encryption, meaning that all messages are encrypted on the sender’s phone and decrypted on the receiver’s phone; no part of the network can eavesdrop on the messages.

Since then, Telegram has been playing cat-and-mouse with the Russian telecom regulator Roskomnadzor by varying the IP address the app uses to communicate. Because Telegram isn’t a fixed website, it doesn’t need a fixed IP address. Telegram bought tens of thousands of IP addresses and has been quickly rotating through them, staying a step ahead of censors. Cleverly, this tactic is invisible to users. The app never sees the change, or the entire list of IP addresses, and the censor has no clear way to block them all.

A week after the court ban, Roskomnadzor countered with an unprecedented move of its own: blocking 19 million IP addresses, many on Amazon Web Services and Google Cloud. The collateral damage was widespread: The action inadvertently broke many other web services that use those platforms, and Roskomnadzor scaled back after it became clear that its action had affected services critical for Russian business. Even so, the censor is still blocking millions of IP addresses.

More recently, Russia has been pressuring Apple not to offer the Telegram app in its iPhone App Store. As of this writing, Apple has not complied, and the company has allowed Telegram to download a critical software update to iPhone users (after what the app’s founder called a delay last month). Roskomnadzor could further pressure Apple, though, including by threatening to turn off its entire iPhone app business in Russia.

Telegram might seem a weird app for Russia to focus on. Those of us who work in security don’t recommend the program, primarily because of the nature of its cryptographic protocols. In general, proprietary cryptography has numerous fatal security flaws. We generally recommend Signal for secure SMS messaging, or, if having that program on your computer is somehow incriminating, WhatsApp. (More than 1.5 billion people worldwide use WhatsApp.) What Telegram has going for it is that it works really well on lousy networks. That’s why it is so popular in places like Iran and Afghanistan. (Iran is also trying to ban the app.)

What the Russian government doesn’t like about Telegram is its anonymous broadcast feature­—channel capability and chats—­which makes it an effective platform for political debate and citizen journalism. The Russians might not like that Telegram is encrypted, but odds are good that they can simply break the encryption. Telegram’s role in facilitating uncontrolled journalism is the real issue.

Iran attempts to block Telegram have been more successful than Russia’s, less because Iran’s censorship technology is more sophisticated but because Telegram is not willing to go as far to defend Iranian users. The reasons are not rooted in business decisions. Simply put, Telegram is a Russian product and the designers are more motivated to poke Russia in the eye. Pavel Durov, Telegram’s founder, has pledged millions of dollars to help fight Russian censorship.

For the moment, Russia has lost. But this battle is far from over. Russia could easily come back with more targeted pressure on Google, Amazon and Apple. A year earlier, Zello used the same trick Telegram is using to evade Russian censors. Then, Roskomnadzor threatened to block all of Amazon Web Services and Google Cloud; and in that instance, both companies forced Zello to stop its IP-hopping censorship-evasion tactic.

Russia could also further develop its censorship infrastructure. If its capabilities were as finely honed as China’s, it would be able to more effectively block Telegram from operating. Right now, Russia can block only specific IP addresses, which is too coarse a tool for this issue. Telegram’s voice capabilities in Russia are significantly degraded, however, probably because high-capacity IP addresses are easier to block.

Whatever its current frustrations, Russia might well win in the long term. By demonstrating its willingness to suffer the temporary collateral damage of blocking major cloud providers, it prompted cloud providers to block another and more effective anti-censorship tactic, or at least accelerated the process. In April, Google and Amazon banned­—and technically blocked­—the practice of “domain fronting,” a trick anti-censorship tools use to get around Internet censors by pretending to be other kinds of traffic. Developers would use popular websites as a proxy, routing traffic to their own servers through another website­—in this case Google.com­—to fool censors into believing the traffic was intended for Google.com. The anonymous web-browsing tool Tor has used domain fronting since 2014. Signal, since 2016. Eliminating the capability is a boon to censors worldwide.

Tech giants have gotten embroiled in censorship battles for years. Sometimes they fight and sometimes they fold, but until now there have always been options. What this particular fight highlights is that Internet freedom is increasingly in the hands of the world’s largest Internet companies. And while freedom may have its advocates—­the American Civil Liberties Union has tweeted its support for those companies, and some 12,000 people in Moscow protested against the Telegram ban­—actions such as disallowing domain fronting illustrate that getting the big tech companies to sacrifice their near-term commercial interests will be an uphill battle. Apple has already removed anti-censorship apps from its Chinese app store.

In 1993, John Gilmore famously said that “The Internet interprets censorship as damage and routes around it.” That was technically true when he said it but only because the routing structure of the Internet was so distributed. As centralization increases, the Internet loses that robustness, and censorship by governments and companies becomes easier.

This essay previously appeared on Lawfare.com.

Posted on June 13, 2018 at 6:55 AMView Comments

Sidebar photo of Bruce Schneier by Joe MacInnis.