libssh vulnerability: Critical flaw in Linux and Mac SSH/SFTP services
Who is using libssh?
Libssh is used mostly to allow secure connections between server and clients. It is used for secure file transfers (secure FTP) between different computers in projects like KDE and produces secure connections in projects like Github and X2Go etc. l
How an attacker can gain access to your server?
Instead of request to authenticate in the system, an attacker can send a request that authentication is already successful and gain up to the highest permissions and execute absolutely arbitrary code. In fact, attacker presents the server a SSH2_MSG_USERAUTH_SUCCESS message
in place of the SSH2_MSG_USERAUTH_REQUEST message which the server would expect
to initiate authentication.
Which devices are affected?
Servers that are using libssh versions 0.6 and above are vulnerable
How to check if you’re vulnerable?
You can easily check whether you are vulnerable using code below:
https://github.com/leapsecurity/libssh-scanner
How to fix up?
To fix this vulnerability you should visit the official site
https://www.libssh.org/2016/02/23/libssh-0-7-3-security-and-bugfix-release/
and update your libssh library.
Reference:
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2018-10933
https://www.libssh.org/2018/10/16/libssh-0-8-4-and-0-7-6-security-and-bugfix-release/
https://www.libssh.org/security/advisories/CVE-2018-10933.txt
Get the Help You Need
Cybersecurity is our core expertise. Let’s get in touch and you will learn more about how UnderDefense can benefit your organization
Next Readers
Splunk ES vs. Elastic (ELK) Stack: Comparison from the SOC Analyst
Splunk ES vs. Elastic (ELK) Stack: Comparison from the SOC Analystby Iryna Yamborska1. What are Splunk ES and Elastic (ELK) Stack? 2. Main Differences Between Splunk ES and Elastic (ELK) Stack 3. Summary Comparison 4. ConclusionThe modern digital and globalized world...
Log4Shell: How to Mitigate Log4j Vulnerability
Log4Shell: How to Mitigate Log4j Vulnerability (CVE-2021-44228, CVE-2021-45046, CVE-2021-4104)by Iryna Yamborska1. What is Log4Shell? 2. What makes Log4j uniquely dangerous even though you seem protected 3. Which Version is not affected? 4. How to Mitigate the...
Average Penetration Testing Cost. The Real Value of Security Test
Average Penetration Testing Cost. The Real Value of Security Test1. Do I Really Need Penetration Testing? 2. Why, When, and How Often to Perform a Penetration Test? 3. What is Penetration Testing? 4. Which Type of Penetration Test Should I Choose? 5. How Much Does...