CVE-2026-66353: Doggo vulnerable to cross-site scripting via unescaped date field values

Severity: medium (CVSS 5.3 v4.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.5% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-08-27 · updated 2026-09-01
Weakness: CWE-79

Description

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in woylie doggo allows Reflected XSS. Doggo.normalize_value/2 in lib/doggo.ex returned date field values wrapped in {:safe, ...}, the Phoenix.HTML marker meaning "already escaped, emit verbatim", without escaping them, so the value reached the value attribute of the <input> rendered by the field component unchanged. Any application rendering <.field type="date"> over user-controlled params is affected through the ordinary Phoenix form round-trip, where a failed validation re-renders the submitted value. The pattern kept exactly the first ten bytes and discarded shorter values, capping a payload at ten bytes: enough to terminate the attribute and open an element or attach a short event handler, not enough to place attacker-chosen script inline. Only type="date" is affected. This issue affects doggo: from 0.1.0 before 0.14.8.

Affected products

woylie doggo: from 0.1.0 before 0.14.8 — fixed in 0.14.8

How to fix

Upgrade to a fixed version: woylie doggo 0.14.8. Check the vendor advisory for mitigations.

References

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