[Cyber Security Terms](/glossary) Web Shell [Blog](/blog)[Breaches](/breaches)[Resources](/resources)[News](/news) [Cyber Security Terms](/glossary) # Web Shell ##### [Edward Kost](/team/edward-kost) updated Sep 24, 2021 ###### Contents ## What is a Web Shell? A web shell attack is the process of injecting an infected script into a web server so that malicious commands can be issued to the compromised server from a web browser. A web shell attack could facilitate the following: * Sensitive data theft. * A [DDoS attack](https://www.upguard.com/blog/what-is-a-ddos-attack). * Forced recruitment [into a botnet](https://www.upguard.com/blog/what-is-a-botnet). * The installation of [Ransomware](https://www.upguard.com/blog/ransomware). Backdoors are most efficiently established with web shells. Because of this, cyberattacks rarely immediately follow a web shell injection. Usually, cybercriminals are implementing an access point for future attacks. ## Key takeaways * The best form of defense is to remediate the security vulnerabilities that could facilitate web shell injections. * Web shells are primarily used as persistence mechanisms. * To mitigate successful web shell injections, It’s important to keep web server software and all third-party software updated with the latest security patches. * * ###### Reviewed by No items found. ###### Author ##### [Edward Kost](/team/edward-kost) ###### Reviewed by ##### [Kaushik Sen](/team/kaushik-sen) ###### Join 27,000+ cybersecurity newsletter subscribers ## Read more about Web Shells Learn more about Web Shell and the latest issues in cybersecurity. [UpGuard](/blog/what-are-web-shell-attacks) [What are Web Shell Attacks? How to Protect Your Web Servers](/blog/what-are-web-shell-attacks) #### [What are Web Shell Attacks? How to Protect Your Web Servers](/blog/what-are-web-shell-attacks) Web shell attacks have doubled between 2021 and 2020. Learn about this threat and how to protect your web server. [](/team/edward-kost) [Edward Kost](#) December 10, 2025 [View all blog posts](/blog) ## See UpGuard In Action Book a free, personalized onboarding call with one of our cybersecurity experts. [Contact sales](/demo) [Free demo](/demo) ## More from our blog Learn more about the latest issues in cybersecurity. [UpGuard](/blog/find-out-if-youre-exposed-on-the-dark-web) [Find Out if You're Exposed on the Dark Web](/blog/find-out-if-youre-exposed-on-the-dark-web) #### [Find Out if You're Exposed on the Dark Web](/blog/find-out-if-youre-exposed-on-the-dark-web) Answer 5 quick questions to predict what a dark web scan will find about your company. Then run the free scan to see your real exposure. 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[](/team/revashni-moodley) [Revashni Moodley](#) October 14, 2026 [UpGuard](/blog/good-security-rating-your-dark-web-exposure-says-otherwise) [Good Security Rating? Your Dark Web Exposure Says Otherwise](/blog/good-security-rating-your-dark-web-exposure-says-otherwise) #### [Good Security Rating? Your Dark Web Exposure Says Otherwise](/blog/good-security-rating-your-dark-web-exposure-says-otherwise) Scan your domain to see just how exposed you are on the Dark Web. [](/team/lance-turner) [Lance Turner](#) October 11, 2026 [View all blog posts](/blog) ### Sign up for our newsletter UpGuard's monthly newsletter cuts through the noise and brings you what matters most: our breaking research, in-depth analysis of emerging threats, and actionable strategic insights. ##### Free instant security score ## How secure is your organization? 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