Friday, July 19, 2024
EHA

7 Years Old Critical Linux Privilege Escalation Bug Let Hackers Gain Root Access

GitHub security researcher Kevin Backhouse has recently discovered a seven-year-old critical Linux privilege escalation bug in the polkit system service, which was previously called PoilcyKit, which could allow any hackers to bypass authorization to gain root access on the affected system.

If you don’t know the work of polkit, then let me justify it in short; it’s a toolkit, and if an application needs root privileges for a task, then polkit asks for the appropriate or relevant password.

The recently discovered bug has been tracked as, CVE-2021-3560 and it’s mainly found in polkit service that is actually associated with a typical Linux system and service manager component, “systemd.”

Seven-year-old Polkit Flaw

This vulnerability was integrated into Commit bfa5036b which was introduced seven years ago, and this bug explored several paths in various Linux distributions since it’s initially directed in polkit version 0.113.

  • CVE ID: CVE-2021-3560
  • CVSS v3 Base Score: 7.8
  • Attack Vector: Local
  • Privileges Required: Low
  • User Interaction: None
  • Integrity Impact: High

This bug requires only a few commands using the terminal tools like bash, kill, and dbus-send, in short, this bug is easy to exploit.

By starting a dbus-send command this bug could be triggered, but, when polkit is still in the midst of concocting the request, it kills it. When polkit asks for the UID of a connection that doesn’t exist, an error arises due to the execution of this during the midst of an authentication request.

Vulnerable Distributions

Here’s the list of all the distribution that are vulnerable to this bug:-

  • RHEL 8: Yes
  • Fedora 21 (or later): Yes
  • Debian testing (“bullseye”): Yes
  • Ubuntu 20.04: Yes

Exploitation

Kevin Backhouse notes that this bug is a possible privilege escalation that was very easy and quick to execute and with only a few commands it can be exploited.

Here, the query that had already ended incorrectly the polkit handles it. Instead of canceling the process, Polkit feigned that the request had come from a process with the UID 0.

This implies that here in this stage the Polkit simply assumes this process request arrived from a root process, and it immediately approves the request. Though this didn’t always work perfectly, but still it is frequently enough to keep the effort low.

Mitigation

According to the Red Hat report, currently, there are no such proper mitigations are available, if any available then they don’t need the criteria of Red Hat Product Security.

However, to remediate any possible risk that may emerge due to this bug, the experts have strongly recommended every user to immediately update their Linux installations as soon as possible.

Website

Latest articles

Hackers Claiming Dettol Data Breach: 453,646 users Impacted

A significant data breach has been reported by a threat actor known as 'Hana,'...

CrowdStrike Update Triggers Widespread Windows BSOD Crashes

A recent update from cybersecurity firm CrowdStrike has caused significant disruptions for Windows users,...

Operation Spincaster Disrupts Approval Phishing Technique that Drains Victim’s Wallets

Chainalysis has launched Operation Spincaster, an initiative to disrupt approval phishing scams that have...

Octo Tempest Know for Attacking VMWare ESXi Servers Added RansomHub & Qilin to Its Arsenal

Threat actors often attack VMware ESXi servers since they accommodate many virtual machines, which...

TAG-100 Actors Using Open-Source Tools To Attack Gov & Private Orgs

Hackers exploit open-source tools to execute attacks because they are readily available, well-documented, and...

macOS Users Beware Of Weaponized Meeting App From North Korean Hackers

Meeting apps are often targeted and turned into weapons by hackers as they are...

Hackers Exploiting Legitimate RMM Tools With BugSleep Malware

Since October 2023, MuddyWater, which is an Iranian threat group linked to MOIS, has...
Balaji
Balaji
BALAJI is an Ex-Security Researcher (Threat Research Labs) at Comodo Cybersecurity. Editor-in-Chief & Co-Founder - Cyber Security News & GBHackers On Security.

Free Webinar

Low Rate DDoS Attack

9 of 10 sites on the AppTrana network have faced a DDoS attack in the last 30 days.
Some DDoS attacks could readily be blocked by rate-limiting, IP reputation checks and other basic mitigation methods.
More than 50% of the DDoS attacks are employing botnets to send slow DDoS attacks where millions of IPs are being employed to send one or two requests per minute..
Key takeaways include:

  • The mechanics of a low-DDoS attack
  • Fundamentals of behavioural AI and rate-limiting
  • Surgical mitigation actions to minimize false positives
  • Role of managed services in DDoS monitoring

Related Articles