What is the CVSS score of CVE-2025-65019?

CVE-2025-65019 has a CVSS 3.1 base score of 5.4 (Medium). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N. EPSS exploitation probability: 0.1%.

Which versions of Astro are affected by CVE-2025-65019?

Organizations using Astro should be aware of moderate risk from CVE-2025-65019, a cross-site scripting vulnerability rated CVSS 5.4.. A patch is available.

Is there a public PoC exploit available for CVE-2025-65019?

Yes, a public proof-of-concept exploit is available for CVE-2025-65019. Prioritise patching immediately. EPSS: 0.1%.

How to fix or mitigate CVE-2025-65019?

Within 30 days: Identify affected systems and apply vendor patches as part of regular patch cycle. Verify Content-Security-Policy and output encoding.

Astro CVE-2025-65019

MEDIUM

Cross-site Scripting (XSS) (CWE-79)

2025-11-19 security-advisories@github.com

XSS Astro

5.4

CVSS 3.1 · GitHub Advisory

Severity by source

GitHub Advisory PRIMARY

5.4 MEDIUM

AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N

Primary rating from GitHub Advisory · only source for this CVE.

CVSS VectorGitHub Advisory

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

Required

Scope

Unchanged

Confidentiality

Low

Integrity

Low

Availability

None

Lifecycle Timeline

Analysis Generated

Mar 28, 2026 - 19:23 vuln.today

Patch released

Mar 28, 2026 - 19:23 nvd

Patch available

PoC Detected

Nov 25, 2025 - 15:09 vuln.today

Public exploit code

CVE Published

Nov 19, 2025 - 17:15 nvd

MEDIUM 5.4

DescriptionGitHub Advisory

Astro is a web framework. Prior to version 5.15.9, when using Astro's Cloudflare adapter (@astrojs/cloudflare) with output: 'server', the image optimization endpoint (/_image) contains a critical vulnerability in the isRemoteAllowed() function that unconditionally allows data: protocol URLs. This enables Cross-Site Scripting (XSS) attacks through malicious SVG payloads, bypassing domain restrictions and Content Security Policy protections. This issue has been patched in version 5.15.9.

AnalysisAI

Astro is a web framework. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available.

Technical ContextAI

This vulnerability is classified as Cross-Site Scripting (XSS) (CWE-79), which allows attackers to inject malicious scripts into web pages viewed by other users. Astro is a web framework. Prior to version 5.15.9, when using Astro's Cloudflare adapter (@astrojs/cloudflare) with output: 'server', the image optimization endpoint (/_image) contains a critical vulnerability in the isRemoteAllowed() function that unconditionally allows data: protocol URLs. This enables Cross-Site Scripting (XSS) attacks through malicious SVG payloads, bypassing domain restrictions and Content Security Policy protections. This issue has been patched in version 5.15.9. Affected products include: Astro. Version information: version 5.15.9.

RemediationAI

A vendor patch is available. Apply the latest security update as soon as possible. Sanitize all user input, use Content-Security-Policy headers, encode output contextually (HTML, JS, URL). Use frameworks with built-in XSS protection.