Answer in brief
CVE-2026-126362 records a Low severity (CVSS 2.3) vulnerability in Astro: Reflected XSS via unescaped slot names in @astrojs/svelte. The current sources do not mark it as known exploited. The current feed maps withastro/astro (generic), @astrojs/svelte (npm), @astrojs/svelte (npm). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 2.3. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps withastro/astro (generic), @astrojs/svelte (npm), @astrojs/svelte (npm). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| withastro/astrogeneric | >=5.7.3 <9.1.2 | 9.1.2 |
| @astrojs/sveltenpm | >=5.7.3,<=9.1.1 | 9.1.2 |
| @astrojs/sveltenpm | >=5.7.3,<=9.1.1 | 9.1.2 |
Published upstream
Nov 12, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Nov 12, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Nov 12, 2026
Astro is a web framework for content-driven websites. From 5.7.3 until 9.1.2, the @astrojs/svelte renderer inserted a named slot into the quoted name attribute of an astro-slot wrapper without HTML escaping. Request-controlled slot names containing a quote could terminate the attribute and inject active HTML. Exploitation required a hydrated Svelte component using a client:* directive and dynamic rendering of the attacker-chosen slot; components that did not render that slot emitted only Astro's escaped fallback content. Both server rendering and client-side hydration used the unsafe slot name. This issue is fixed in version 9.1.2.
Quoted source text, attributed separately from HOL analysis.