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TI-2026-26148 Aliases CVE-2026-33769GHSA-g735-7g2w-hh3f

Astro: Remote allowlist bypass via unanchored matchPathname wildcard

Priority MEDIUM 48CWE-20Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
Present
Impact type
—
Confidentiality · integrity · availability
Low · None · None
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and GitHub.

Summary

Astro is a web framework. From version 2.10.10 to before version 5.18.1, this issue concerns Astro's remotePatterns path enforcement for remote URLs used by server-side fetchers such as the image optimization endpoint. The path matching logic for /* wildcards is unanchored, so a pathname that contains the allowed prefix later in the path can still match. As a result, an attacker can fetch paths outside the intended allowlisted prefix on an otherwise allowed host. This issue has been patched in version 5.18.1.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00338 27th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Fixed astro (withastro): 5.18.1astro (npm): 5.18.1

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
withastroastro2.10.10 to before 5.18.15.18.1Patch availableCNA
—astro (npm)2.10.10 to before 5.18.15.18.1Patch availableGHSA-g735-7g2w-hh3f
  • astro Vendorwithastro Affected 2.10.10 to before 5.18.1 Fixed in 5.18.1 Patch available CNA
  • astro (npm) Vendor— Affected 2.10.10 to before 5.18.1 Fixed in 5.18.1 Patch available GHSA-g735-7g2w-hh3f

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:astro:astro:*:*:*:*:*:node.js:*:*2.10.10 to before 5.18.1Vulnerablewithastro
  • cpe:2.3:a:astro:astro:*:*:*:*:*:node.js:*:* Versions 2.10.10 to before 5.18.1 Vulnerable ·withastro

Remediation

  • Fix · CNA astro (withastro) Fixed in 5.18.1
  • Fix · GHSA-g735-7g2w-hh3f astro (npm) Fixed in 5.18.1 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-33769
  2. 2026-10-03 Alias added: GHSA-g735-7g2w-hh3f

References

Exploit 1

Advisory 1

Other 1

  • TI-2024-37142 Server source code is exposed to the public if sourcemaps are enabled CVSS 4.0HIGH 7.8
  • TI-2025-34958 Unauthorized third-party images in Astro’s _image endpoint CVSS 4.0MEDIUM 6.9
  • TI-2025-39915 Server-side request forgery in withastro astro CVSS 3.1MEDIUM 6.5
  • TI-2025-38274 Astro's `X-Forwarded-Host` is reflected with no validation CVSS 3.1MEDIUM 6.5
  • TI-2026-36915 Astro: Reflected XSS via unescaped slot name CVSS 3.1HIGH 7.1
  • TI-2025-40102 Astro is vulnerable to Reflected XSS via the server islands feature CVSS 3.1HIGH 7.1
See all 19 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences