# SA-2026-003: Article links could inject attributes

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Security advisory SA-2026-003 (medium, fixed): Article links could inject attributes.

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# SA-2026-003: Article links could inject attributes

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|  |  |
|---|---|
| **Severity** | medium |
| **Status** | fixed |
| **Weakness** | CWE-79 |
| **Component** | `admin/build/build.py (article_inline)` |
| **Found by** | security@php.newsroom |
| **Found** | 2026-10-22 |
| **Fixed in** | v0.5.5 |
| **Fixed by** | security@php.newsroom |

## What it is

The article renderer escaped text without escaping quotes, then put link targets into href="...". A link target holding a quote could add attributes, such as an event handler.

## What an attacker could do

Stored XSS through any article text, including guest articles.

**How:** [x](/a" onmouseover="...) in an article became a live handler.

## Root cause

html.escape(quote=False) was used for text that later landed inside an attribute.

## What contributed
- The markdown renderer was hand-written, with regexes, after escaping.

## What was not in place

Escaping matched to the output context, and link targets restricted to a safe character set.

## The fix

Link targets are quoted, escaped and restricted to [A-Za-z0-9/._#-]; https links exclude quotes and spaces.

## What prevents it now

The gate fails on inline event-handler attributes in generated HTML (the check is on the security branch).


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site v0.18.0 · data as of 2026-10-24T16:05Z · vault commit 8c16a64a7cf6 · https://php.oct.2026.newsroom.sgit.ai/admin/appsec/advisories/SA-2026-003/index.html