CVE-2026-33769

Astro: Remote allowlist bypass via unanchored matchPathname wildcard

MEDIUM
5.3
CVSS Score
Published: March 24, 2026 at 06:44 PM UTC
Updated: June 17, 2026 at 10:38 AM UTC
2 products affected across 2 vendorsAstroAstro

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Severity
MEDIUM5.3
Exploit prediction
EPSS 0.3%
SSVC
PoC

Description

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

2.10.10 ≤ v < 5.18.1
v < 5.18.1
Affected range stops below 5.18.1, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (1)

x_refsource_CONFIRMExploitVendor Advisory
Source: cverecord
https://github.com/withastro/astro/security/advisories/GHSA-g735-7g2w-hh3f

SSVC — Action Prioritization

SSVCPoCNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
LOW
Integrity
NONE
Availability
NONE
Vector?

Quick Info

StatusANALYZED
CWE
CWE-20

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