Connect with us

Hi, what are you looking for?



Serious Vulnerability in Blackphone Exposed Messages, Location

A serious vulnerability in the privacy-focused Blackphone could have been exploited by a remote attacker to execute arbitrary code on a targeted device, a researcher revealed on Tuesday.

A serious vulnerability in the privacy-focused Blackphone could have been exploited by a remote attacker to execute arbitrary code on a targeted device, a researcher revealed on Tuesday.

According to Mark Dowd, director and founder of Australia-based Azimuth Security, the vulnerability existed in Silent Text, the Blackphone messaging application developed by Silent Circle. The app, which allows users to send text messages and files securely, is also available for other types of smartphones running Android and iOS.

Dowd identified a memory corruption (type confusion) vulnerability that allowed an attacker to execute arbitrary code with the privileges of the messaging application. The flaw could have been leveraged by a hacker to decrypt messages, take over Silent Circle accounts, access contacts, collect location information, and write data to external storage. An attacker could have also executed a privilege escalation exploit that would enable him to take complete control of the targeted handset.

When users send messages or files through Silent Text, the information is delivered over an encrypted channel that uses the Silent Circle Instant Message Protocol (SCIMP).

“SCIMP provides end-to-end encryption, so that data exchanged in a given conversation cannot be decrypted by an eavesdropping third party (including Silent Circle),” Dowd explained in a blog post. “The SCIMP implementation supplied with SilentText contains a type confusion vulnerability, that allows an attacker to directly overwrite a pointer in memory (either partially or in full), which when successfully exploited can be used to gain remote, unauthenticated access to the vulnerable device.”

An attacker could have exploited this vulnerability simply by knowing the targeted user’s Silent Circle ID or phone number. The researcher highlighted that a malicious actor did not necessarily need to trick the victim into contacting him for the attack to work, although this is also an attack vector.

Fortunately, the vulnerability has been addressed by Blackphone and Silent Circle.

Advertisement. Scroll to continue reading.

In September, SGP Technologies, the joint venture between Geeksphone and Silent Circle responsible for the development of Blackphone, announced the launch of a bug bounty program designed to encourage researchers to contribute to making Blackphone and Silent Circle’s communications services more secure.

“We have high expectations for security and privacy. In order to deliver on our expectations we must continually build a strong relationship with the security research community,” Daniel Ford, CSO of SGP Technologies, said at the time.

A detailed technical description of the Blackphone vulnerability is available on Azimuth Security’s blog.

Written By

Eduard Kovacs (@EduardKovacs) is a contributing editor at SecurityWeek. He worked as a high school IT teacher for two years before starting a career in journalism as Softpedia’s security news reporter. Eduard holds a bachelor’s degree in industrial informatics and a master’s degree in computer techniques applied in electrical engineering.

Click to comment

Daily Briefing Newsletter

Subscribe to the SecurityWeek Email Briefing to stay informed on the latest threats, trends, and technology, along with insightful columns from industry experts.

SecurityWeek’s Threat Detection and Incident Response Summit brings together security practitioners from around the world to share war stories on breaches, APT attacks and threat intelligence.


Securityweek’s CISO Forum will address issues and challenges that are top of mind for today’s security leaders and what the future looks like as chief defenders of the enterprise.


Expert Insights

Related Content


Less than a week after announcing that it would suspended service indefinitely due to a conflict with an (at the time) unnamed security researcher...

Data Breaches

OpenAI has confirmed a ChatGPT data breach on the same day a security firm reported seeing the use of a component affected by an...

Risk Management

The supply chain threat is directly linked to attack surface management, but the supply chain must be known and understood before it can be...


The latest Chrome update brings patches for eight vulnerabilities, including seven reported by external researchers.


Patch Tuesday: Microsoft warns vulnerability (CVE-2023-23397) could lead to exploitation before an email is viewed in the Preview Pane.


Apple has released updates for macOS, iOS and Safari and they all include a WebKit patch for a zero-day vulnerability tracked as CVE-2023-23529.

IoT Security

A group of seven security researchers have discovered numerous vulnerabilities in vehicles from 16 car makers, including bugs that allowed them to control car...

IoT Security

A vulnerability affecting Dahua cameras and video recorders can be exploited by threat actors to modify a device’s system time.