CVE-2017-20202

Description

Web Developer for Chrome v0.4.9 contained malicious code that generated a domain via a DGA and fetched a remote script. The fetched script conditionally loaded follow-on modules that performed extensive ad substitution and malvertising, displayed fake “repair” alerts that redirected users to affiliate programs, and attempted to harvest credentials when users logged in. Injected components enumerate common banner sizes for substitution, replace third-party ad calls, and redirect victim traffic to affiliate landing pages. Potential impacts include user-level code execution in the browser context, large-scale ad fraud and traffic hijacking, credential theft, and exposure to additional payloads delivered by the actor. The compromise was reported on by the maintainer of Web Developer for Chrome on August 2, 2017 and remediated in v0.5.0.

Is your site exposed to CVE-2017-20202?

Run a free security scan — no signup, results in seconds.

Weakness Type (CWE)

CWE-506 CWE-506

References

Other References

https://chromewebstore.google.com/detail/web-developer/bfbameneiokkgbdmiekhjnmfkcnldhhm?pli=1 https://gist.github.com/piedpiperRichard/076516da60f45842f1a6e6ae35a9a240/ https://ui.vision/blog/chrome-extension-adware/ https://web.archive.org/web/20170803163618/https://chrispederick.com/blog/web-developer-for-chrome-compromised/ https://www.proofpoint.com/us/threat-insight/post/threat-actor-goes-chrome-extension-hijacking-spree https://www.vulncheck.com/advisories/web-developer-for-chrome-malicious-backdoor-supply-chain-compromise https://www.proofpoint.com/us/threat-insight/post/threat-actor-goes-chrome-extension-hijacking-spree

Frequently Asked Questions

What is CVE-2017-20202? +

Web Developer for Chrome v0.4.9 contained malicious code that generated a domain via a DGA and fetched a remote script. The fetched script conditionally loaded follow-on modules that performed extensive ad substitution and malvertising, displayed fake “repair” alerts that redirected users to affiliate programs, and attempted to harvest credentials when users logged in. Injected components enumerate common banner sizes for substitution, replace third-party ad calls, and redirect victim traffic to affiliate landing pages. Potential impacts include user-level code execution in the browser context, large-scale ad fraud and traffic hijacking, credential theft, and exposure to additional payloads delivered by the actor. The compromise was reported on by the maintainer of Web Developer for Chrome on August 2, 2017 and remediated in v0.5.0.

How do I check if I'm vulnerable to CVE-2017-20202? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

Related Vulnerabilities

CVE-2026-44484

PyTorch Lightning is a deep learning framework to pretrain and finetune AI models. Versions 2.6.2 and 2.6.2 have introduced functionality …

CVE-2026-46421

The SAP Cloud Application Programming Model is a tool for building enterprise-grade cloud applications, and cap-js/cds-dbs is the monorepo for …

CVE-2017-20201

CCleaner v5.33.6162 and CCleaner Cloud v1.07.3191 (32-bit builds) contained a malicious pre-entry-point loader that diverts execution from __scrt_common_main_seh into a …

CVE-2018-25117

VestaCP commit a3f0fa1 (2018-05-31) up to commit ee03eff (2018-06-13) contain embedded malicious code that resulted in a supply-chain compromise. New …

CVE-2025-59038

Prebid.js is a free and open source library for publishers to quickly implement header bidding. NPM users of prebid 10.9.2 …

CVE-2025-59039

Prebid Universal Creative (PUC) is a JavaScript API to render multiple formats. Npm users of PUC 1.17.3 or PUC latest …