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medium·Product Based Web Vulnerabilities·Updated Dec 16, 2023

CVE-2021-30151 Scanner

Detects 'Cross-Site Scripting (XSS)' vulnerability in Sidekiq affects v. through 5.1.3 and 6.x through 6.2.0.

Est. Time~15 seconds
Scan TypeSingle Scan
Targetsurl
CostFree
2.5k
Times Used
continuous scan runs
4.8k
Continuously Checked
assets under CS
0
Vulnerabilities Found
confirmed findings
References
CVECVE-2021-30151
6.1
CVSS

Sidekiq through 5.1.3 and 6.x through 6.2.0 allows XSS via the queue name of the live-poll feature when Internet Explorer is used.

Attack Vector
-
Privileges Req.
-
User Interaction
-
Affected
n/aby n/a
n/a
Updated Aug 21, 2026View on NVD →
Detail

Sidekiq is a background processing framework in Ruby that is responsible for executing time-consuming jobs that would otherwise block the main application. It is an excellent tool that helps manage long-running and computationally intensive tasks without diminishing application responsiveness. This open-source project has a thriving community of developers and users who rely on it to streamline their workloads.

CVE-2021-30151 is a significant vulnerability found in Sidekiq versions 5.1.3 and 6.x through 6.2.0. This flaw specifically arises when using the live-poll feature in combination with Internet Explorer. Attackers can exploit this bug to execute cross-site scripting (XSS) attacks through the queue name, causing harm to users' computers. This type of attack entails injecting malicious code into web-based applications to manipulate or bypass standard security mechanisms, resulting in unauthorized operations.

When exploited, CVE-2021-30151 can have significant repercussions. Hackers can use this vulnerability to plant their malicious code on the affected system, steal sensitive information from the user, and execute malicious commands on the user's behalf. Due to the nature of cross-site scripting, it can be challenging to detect and trace the origin of the threat. This vulnerability can also degrade system performance and reliability, ultimately impacting business operations.

In conclusion, Sidekiq is an excellent tool for managing background processes in web applications. However, the discovery of CVE-2021-30151 highlights the need for proper vulnerability management and proactive measures to protect against security threats. By following our recommended steps and using s4e.io's professional features, you can take significant steps towards safeguarding your system from malicious actors.

 

REFERENCES

Solution Advice

Taking adequate precautions can help protect your system from CVE-2021-30151 and other similar vulnerabilities. Here are some measures you can take to safeguard against exploitation:

  • Regularly update your Sidekiq version to the latest release to prevent attackers from exploiting known security vulnerabilities.
  • Consider disabling the live-poll feature if you are not using it actively.
  • Implement input validation techniques to ensure user-supplied data is not harmful.
  • Use content security policies (CSP) to prevent the execution of untrusted content.
  • Educate users on the risks of cross-site scripting attacks and how to identify and avoid them.

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CVE-2021-30151 scanner - Cross-Site Scripting (XSS) vulnerability in Sidekiq | S4E