Vulnerability · Published Jul 8, 2026 · Assigned by GitHub_M

CVE-2026-59731Astro 6.4.7 Authorization Bypass via Decode Iteration Limit and Rewrite Path Canonicalization Mismatch

High 8.2

In plain English

A high-severity security flaw in astro from withastro. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 26% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)8.2High

Exploit odds (30 days)0.3%top 73.5% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

Astro is a web framework for content-driven websites. Version 6.4.7 performs authorization decisions on a partially decoded pathname after reaching the iterative URL decoder limit, while later rewrite route matching performs an additional decodeURI() operation and can resolve the request to a protected route. This issue is fixed in version 6.4.8.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
npm	astro	6.4.8	GHSA-vj59-8hwv-xxmv

Affected products (as reported)

Vendor	Product	Versions
withastro	astro	>= 6.4.7, < 6.4.8

Weakness: CWE-647 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N

References

https://github.com/withastro/astro/security/advisories/GHSA-vj59-8hwv-xxmv x_refsource_CONFIRM
https://github.com/withastro/astro/pull/17109 x_refsource_MISC
https://github.com/withastro/astro/commit/27c80ea92248993e5fce94b2c26d87d611ab6785 x_refsource_MISC
https://github.com/withastro/astro/releases/tag/astro@6.4.8 x_refsource_MISC