Telegram for Windows Vulnerability

A vulnerability has been found in Telegram for Windows which allows an attacker to disguise file extensions for attachments.

Threat ID:: CC-2068
Category:: Trojan
Threat Severity:: Low
Threat Vector:
Published:: 22 February 2018 12:00 AM

Report a cyber attack: call 0300 303 5222 or email [email protected]

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Summary

A vulnerability has been found in Telegram for Windows which allows an attacker to disguise file extensions for attachments.

Affected platforms

The following platforms are known to be affected:

Telegram for Windows

Telegram for Windows - All versions prior to 13/02/2018

Threat details

By using the Unicode right-to-left text flow override character within the file name, it is possible to make a malicious file appear to have a safe extension such as png or jpg. This increases the probability of a user opening the file. The vulnerability is currently being exploited to distribute cryptocurrency mining malware.

Remediation steps

Type	Step
	The application should be updated to the latest version. To prevent and detect a trojan infection, ensure that: A robust program of education and awareness training is delivered to users to ensure they don’t open attachments or follow links within unsolicited emails. All operating systems, antivirus and other security products are kept up to date. All day to day computer activities such as email and internet are performed using non-administrative accounts. Strong password policies are in place and password reuse is discouraged. Network, proxy and firewall logs should be monitored for suspicious activity. User accounts accessed from infected machines should be reset on a clean computer.

Type

Step

The application should be updated to the latest version.

To prevent and detect a trojan infection, ensure that:

A robust program of education and awareness training is delivered to users to ensure they don’t open attachments or follow links within unsolicited emails.
All operating systems, antivirus and other security products are kept up to date.
All day to day computer activities such as email and internet are performed using non-administrative accounts.
Strong password policies are in place and password reuse is discouraged.
Network, proxy and firewall logs should be monitored for suspicious activity.
User accounts accessed from infected machines should be reset on a clean computer.

Last edited: 17 February 2020 12:55 pm