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CVE-2017-20202 Detail

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.


Metrics

NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

Nist CVSS score does not match with CNA score
CNA:  VulnCheck
CVSS-B 9.3 CRITICAL
Vector:  CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:N/SC:H/SI:H/SA:N

References to Advisories, Solutions, and Tools

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

Weakness Enumeration

CWE-ID CWE Name Source
CWE-506 Embedded Malicious Code VulnCheck  

Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2017-20202
NVD Published Date:
10/08/2025
NVD Last Modified:
10/08/2025
Source:
VulnCheck