CVE-2026-117645: Phoenix.HTML vulnerable to attribute injection via unvalidated attribute names in attributes_escape/1
phoenixframework · phoenix_html
Vendor fix available · Affected: phoenixframework phoenix_html · Exploitation: unlikely (under 1%)
Not in CyberSIXT coverage yet: no article names this CVE. This page shows the public record.
Higher than 24% of scored CVEs
DescriptionCVE.org
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in phoenixframework phoenix_html allows an attacker who controls attribute names to inject attributes and script into rendered HTML via Phoenix.HTML.attributes_escape/1. attributes_escape/1 in lib/phoenix_html.ex escapes attribute values but not attribute names. key_escape/1 passes a binary key through html_escape, which neutralizes quotes and angle brackets but not whitespace, so a key such as x onmouseover ends the attribute and starts a new one. An atom key is only dasherized, so any character passes, including quotes and >. Nested data, aria and phx keys take the same paths. An application is affected when it builds attribute keys from untrusted input and renders them through HEEx <tag {@attrs}>, content_tag/3, or a direct call. Before 3.0.0 the same code lived in Phoenix.HTML.Tag. This issue affects phoenix_html: from 1.0.0 before 3.3.5 and from 4.0.0 before 4.4.0.
Affected products2
From the CVE record. A product or version that is not listed is unknown, not unaffected.
- phoenixframework · phoenix_htmlfrom 1.0.0 before 3.3.5; from 4.0.0 before 4.4.0
- phoenixframework · phoenix_htmlVersions not stated
On the Atlas
Every published CVE is on the CyberSIXT Atlas, grouped by weakness, vendor and month.
- Exploitation
- Unlikely (under 1%). EPSS under 1%, or no score yet.
- CISA KEV
- Not listed
- Public check
- No public nuclei template
- Weakness
- Cross-site Scripting
- Vendor
- phoenixframework
- Published
- October 2026
CoverageNo articles yet
No CyberSIXT article names CVE-2026-117645 yet, so there is no coverage timeline, action brief or change log for it. Everything on this page comes from the public CVE record, CISA KEV, EPSS and the nuclei template index. Search the archive or see the CVEs in the news.