Phlex vulnerable to Cross-site Scripting (XSS) via maliciously formed HTML attribute names and values

Not analysed yet

We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.

Severity and exploitation

• CISA KEV Not listed.
• EPSS 0.0071, the 53rd percentile, on 6 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

Timeline

1. 31 Oct 2026, 15:16 UTC First seen by agentprime
2. 31 Oct 2026, 15:16 UTC Confirmed by OSV

Sources

• GitHub Advisory Database: GHSA-9p57-h987-4vgx
• OSV: GHSA-9p57-h987-4vgx
• github.com/phlex-ruby/phlex/security/advisories/GHSA-9p57-h987-4vgx
• nvd.nist.gov/vuln/detail/CVE-2024-32970
• github.com/phlex-ruby/phlex/commit/da8f94342a84cff9d78c98bcc3b3604ee2e577d2
• developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy
• developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy#unsafe-inline
• github.com/payloadbox/xss-payload-list
• github.com/phlex-ruby/phlex
• github.com/rubysec/ruby-advisory-db/blob/master/gems/phlex/CVE-2024-32970.yml
• rubygems.org/gems/phlex
• rubygems.org/gems/phlex/versions/1.10.2
• rubygems.org/gems/phlex/versions/1.9.3

Facts on this page come from the GitHub Advisory Database (CC-BY 4.0), OSV and the other sources listed, as published. We don’t reproduce full advisory descriptions, which can contain exploit code.