CVE-2025-64764: Astro is vulnerable to Reflected XSS via the server islands feature
- Is it exploited?
Reported, not confirmed by CISA. VulnCheck KEV lists it as exploited in the wild. CISA has not added it to its Known Exploited Vulnerabilities catalog as of .
VulnCheck KEV lists it since . It cites 1 public report, the first from .
- How likely is exploitation in the next 30 days?
- 0.5%
EPSS score, percentile 44.7 of all scored records. A probability estimated by FIRST, not a report of exploitation.
CISA's SSVC assessment in the CVE record lists exploitation as poc.
- How severe?
- 7.1 High
CVSS v3.1 base score, given by the CNA
- What should I do?
CISA has set no required action, because the vulnerability is not in KEV.
The CVE record links no vendor advisory, patch or mitigation.
- Which versions are affected?
Affected
- < 5.15.8
Source: CISA KEV 2026.10.29, as of ; VulnCheck KEV, as of ; FIRST EPSS, as of ; CVE List, as of . About the data.
Description
Astro is vulnerable to Reflected XSS via the server islands feature
Astro is a web framework. Prior to version 5.15.8, a reflected XSS vulnerability is present when the server islands feature is used in the targeted application, regardless of what was intended by the component template(s). This issue has been patched in version 5.15.8.
Source: CVE List, as of . About the data.
What to do
Advisories and patches
The CVE record links no vendor advisory, patch or mitigation.
This summary is based on the CVE record as of . Check the vendor's advisory before you act: affected versions and fixes can change.
Affected products and versions
Versions by product, as listed in the CVE record (1 product)
| Status | Versions |
|---|---|
| Affected | < 5.15.8 |
Source: CVE List, as of . About the data.
Weakness
CWE-80
- CWE-80: Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS)
CWE and CAPEC are maintained by MITRE; the entries are those named in the CVE record.
Timeline
| Date | Event |
|---|---|
| CVE record published |