Subdomain Takeover in Interactsh serverGHSA-m36x-mgfh-8g78
MEDIUMFix: projectdiscovery/interactsh#155GHSA-m36x-mgfh-8g78 is a medium-severity (CVSS 6.1) Cross-site Scripting (XSS) vulnerability in github.com/projectdiscovery/interactsh. A fix is available for github.com/projectdiscovery/interactsh — see the affected versions and patch details below.
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
Exploitation and automatability from CISA’s SSVC triage for GHSA-m36x-mgfh-8g78.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
GHSA-m36x-mgfh-8g78 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.
Where this sits among everything scored
Of 385,987 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.
Real-World Exposure
github.com/projectdiscovery/interactshReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
A domain configured with interactsh server was vulnerable to subdomain takeover for specfic subdomain, i.e app, Interactsh server before < 1.0.0 used to create cname entries for app pointing to projectdiscovery.github.io as default which intended to used for hosting interactsh web client using GitHub pages. It turns out to be a security issue with a self-hosted interactsh server in which the user may not have configured a web client but still have a cname entry pointing to GitHub pages, making them vulnerable to subdomain takeover.
This issue was initially reported to us as a subdomain takeover for one of our domains that runs interactsh server by Melih at [email protected], and after conducting an internal investigation, we determined that it was an issue with the default config of interactsh server affecting all the server running self-hosted instance of interactsh, as a result - cname entry has been removed in the latest release.
Impact
This allows one to host / run arbitrary client side code (XSS) in a user's browser when browsing the vulnerable subdomain, for more details on the impact, please read this detailed blogpost from Detectify.
Patches
Update to Interactsh server v1.0.0 with go install -v github.com/projectdiscovery/interactsh/cmd/interactsh-server@latest
References
https://github.com/projectdiscovery/interactsh/issues/136
For more information
If you have any questions or comments about this advisory:
- Email us at [email protected]
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/projectdiscovery/interactsh | all versions | 1.0.0go get github.com/projectdiscovery/interactsh@v1.0.0 |
Affected Products
interactshprojectdiscoveryDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/projectdiscovery/interactsh, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/projectdiscovery/interactsh to 1.0.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-m36x-mgfh-8g78 is resolved across your whole dependency graph.
Workarounds
Escape or sanitise the affected output on the server side rather than relying on client-side filtering, and add a Content-Security-Policy that blocks inline script execution so injected markup cannot run even if it reaches the page.
Frequently Asked Questions
Is GHSA-m36x-mgfh-8g78 in your dependencies?
Find it across Go, including transitive dependencies.