CVE-2025-65019Public exploitNetwork attack vector

Reflected XSS via unconditional data URL redirect

Published Nov 19, 2025 · Updated Nov 19, 2025

Cross-site scripting in Astro before 5.15.9 allows remote attackers to execute script via the Cloudflare adapter's /_image endpoint. The isRemoteAllowed() helper treats every data: URL as authorized, so the adapter redirects a crafted SVG data URL to the browser instead of rejecting it. Exploitation requires server output with @astrojs/cloudflare and a victim who follows the crafted endpoint URL; script runs in that site's browser context.

CVSS severity5.4
Medium
EPSS probability0.26%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Cross-site scripting in Astro before 5.15.9 allows remote attackers to execute script via the Cloudflare adapter's /_image endpoint. The isRemoteAllowed() helper treats every data: URL as authorized, so the adapter redirects a crafted SVG data URL to the browser instead of rejecting it. Exploitation requires server output with @astrojs/cloudflare and a victim who follows the crafted endpoint URL; script runs in that site's browser context.

The record

CVE
CVE-2025-65019
Published
Nov 19, 2025
Updated
Nov 19, 2025
Vendor
Astro Technology Company
Product
Astro
Classifications
CWE-79, CAPEC-591, T1189
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Nov 19, 2025CVE publishedPublication date reported by the CVE source.
  2. Nov 19, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 5.15.9

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Astro Technology Company · Astroversion=< 5.15.9

Published CVSS scores

5.4GitHub Advisory DatabaseCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CAPEC-591Reflected XSS
T1189Drive-by Compromise

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo