No VulnCrest analysis published for this CVE yet. Below is the original CNA/NVD description, unmodified.
Description
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.
Exploits & detection
No public PoC or detection template found yet.
Timeline
- Published: 30 Oct 2026
- Last modified upstream: 06 Nov 2026
Sources & licenses
- CVE / CVSS / CWE
- NVD record ↗ (unmodified). This product uses the NVD API but is not endorsed or certified by the NVD. CVE® © The MITRE Corporation.
- Exploitation
- CISA KEV (CC0) · EPSS by FIRST.org
- References used for the analysis
- https://cna.erlef.org/cves/CVE-2026-117645.html
- https://github.com/phoenixframework/phoenix_html/commit/6ad3a1d7960891a468d54636054a98e11dfb5111
- https://github.com/phoenixframework/phoenix_html/commit/a47dc8944a773b7e9273d9691dc6744ec793f1de
- https://github.com/phoenixframework/phoenix_html/commit/d9e4e6b2d9be49e25fb6d6b4fdbb2008174f01a6
- https://osv.dev/vulnerability/EEF-CVE-2026-117645
- Analysis, summary and remediation
- © VulnCrest