CVE-2017-20202

Oct. 9, 2025, 3:50 p.m.

9.3
Critical

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.

Product(s) Impacted

Vendor Product Versions
Web Developer For Chrome
  • Web Developer
  • *

Weaknesses

Common security weaknesses mapped to this vulnerability.

CWE-506
Embedded Malicious Code
The product contains code that appears to be malicious in nature.

*CPE(s)

Affected systems and software identified for this CVE.

Type Vendor Product Version Update Edition Language Software Edition Target Software Target Hardware Other Information
a web_developer_for_chrome web_developer / / / / / / / /

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

Tags

disclosure@vulncheck.com
CWE-506
2025-10-08
CVE-2017-20202

CVSS Score

9.3 / 10

CVSS Data - 4.0

  • Attack Vector: NETWORK
  • Attack Complexity: LOW
  • Attack Requirements: NONE
  • Privileges Required: NONE
  • User Interaction: ACTIVE
  • Scope:
  • Confidentiality Impact: HIGH
  • Integrity Impact: HIGH
  • Availability Impact: NONE
  • Exploit Maturity: NOT_DEFINED

    • 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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

    View Vector String

Timeline

Published: Oct. 8, 2025, 10:15 p.m.
Last Modified: Oct. 9, 2025, 3:50 p.m.

Status : Awaiting Analysis

CVE has been recently published to the CVE List and has been received by the NVD.

More info

Source

disclosure@vulncheck.com

*Disclaimer: Some vulnerabilities do not have an associated CPE. To enhance the data, we use AI to infer CPEs based on CVE details. This is an automated process and might not always be accurate.