CVE-2017-20202 — Web Developer for Chrome v0

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 redirec

01What is this vulnerability?

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…

02Affected products

03Active exploitation status

Not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog. EPSS is the best forward-looking signal — see the EPSS row above.

04Recommended remediation

• Patch to a fixed version listed in the vendor advisory (see references below).
• Mitigate with WAF rules, network egress filters, or feature flags where the patch is not yet available.
• Hunt historical logs for exploitation indicators — see Detection signatures below.

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Ask SARA in chat to draft a starting detection for this CVE in your stack of choice.

07Related CVEs

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

08Timeline

• Published: 2025-10-08T22:04:12.297Z
• Last modified: 2025-10-14T14:18:49.449Z

09References

• web.archive.org — https://web.archive.org/web/20170803163618/https://chrispederick.com/blog/web-de…
• ui.vision — https://ui.vision/blog/chrome-extension-adware/
• www.proofpoint.com — https://www.proofpoint.com/us/threat-insight/post/threat-actor-goes-chrome-exten…
• gist.github.com — https://gist.github.com/piedpiperRichard/076516da60f45842f1a6e6ae35a9a240/
• chromewebstore.google.com — https://chromewebstore.google.com/detail/web-developer/bfbameneiokkgbdmiekhjnmfk…
• www.vulncheck.com — https://www.vulncheck.com/advisories/web-developer-for-chrome-malicious-backdoor…