GitHub this week disclosed the details of an easy-to-exploit Linux vulnerability that can be leveraged to escalate privileges to root on the targeted system.
The flaw, classified as high severity and tracked as CVE-2021-3560, impacts polkit, an authorization service that is present by default in many Linux distributions.
The security hole was discovered by Kevin Backhouse of the GitHub Security Lab. On Thursday, the researcher published a blog post detailing his findings, as well as a video showing the exploit in action.
A local, unprivileged attacker can use the flaw to escalate privileges to root with only a few commands executed in the terminal.
The vulnerability has been confirmed to impact some versions of Red Hat Enterprise Linux, Fedora, Debian and Ubuntu. A patch for CVE-2021-3560 was released on June 3.
“The bug I found was quite old,” Backhouse said. “It was introduced seven years ago in commit bfa5036 and first shipped with polkit version 0.113. However, many of the most popular Linux distributions didn’t ship the vulnerable version until more recently.”
The vulnerable component, polkit, is a system service designed for controlling system-wide privileges, providing a way for non-privileged processes to communicate with privileged processes.
Backhouse described it as a service that plays the role of a judge, determining whether an action initiated by a user — specifically one that requires higher privileges — can be carried out directly or it requires additional authorization, such as entering a password.
The vulnerability discovered by the researcher is easy to exploit, with just a few commands in the terminal. However, due to some timing requirements, it typically takes a few tries for the exploit to be successful.
Related: Patch Released for Linux Kernel Vulnerability Disclosed at Hacking Contest
Related: Privilege Escalation Bugs Patched in Linux Kernel
Related: Linux Kernel Vulnerabilities Can Be Exploited to Bypass Spectre Mitigations
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.
More from Eduard Kovacs
- Russia Blames US Intelligence for iOS Zero-Click Attacks
- Cisco Acquiring Armorblox for Predictive and Generative AI Technology
- Moxa Patches MXsecurity Vulnerabilities That Could Be Exploited in OT Attacks
- Organizations Warned of Salesforce ‘Ghost Sites’ Exposing Sensitive Information
- Organizations Warned of Backdoor Feature in Hundreds of Gigabyte Motherboards
- Barracuda Zero-Day Exploited to Deliver Malware for Months Before Discovery
- Industrial Giant ABB Confirms Ransomware Attack, Data Theft
- Zyxel Firewalls Hacked by Mirai Botnet
Latest News
- Russia Blames US Intelligence for iOS Zero-Click Attacks
- Toyota Discloses New Data Breach Involving Vehicle, Customer Information
- Cisco Acquiring Armorblox for Predictive and Generative AI Technology
- Moxa Patches MXsecurity Vulnerabilities That Could Be Exploited in OT Attacks
- Amazon Settles Ring Customer Spying Complaint
- Organizations Warned of Salesforce ‘Ghost Sites’ Exposing Sensitive Information
- Adobe Inviting Researchers to Private Bug Bounty Program
- Critical Vulnerabilities Found in Faronics Education Software
