CVE-2026-41067 | Astro: XSS via incomplete `</script>` sanitization in `define:vars` allows case-insensitive and whitespace-based bypass

Exp

Astro is a web framework. Prior to 6.1.6, the defineScriptVars function in Astro's server-side rendering pipeline uses a case-sensitive regex /<\/script>/g to sanitize values injected into inline <script> tags via the define:vars directive. HTML parsers close <script> elements case-insensitively and also accept whitespace or / before the closing >, allowing an attacker to bypass the sanitization with payloads like </Script>, </script >, or </script/> and inject arbitrary HTML/JavaScript. This vulnerability is fixed in 6.1.6.

Published: 2026-04-24 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-41067 is rated Exploit Available (50/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.19%). 1 public exploit reference(s) are indexed (Exploit-DB). Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2026-41067

EDB-ID Source Kind Published Link
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2026-41067

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.05% 0.19% +0.14%
2 2026-06-05 0.03% 0.05% +0.02%
3 2026-04-25 — 0.03% —

Full EPSS history (3 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-41067

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.1 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
 2.8 2.7 [email protected]

Weakness enumeration for CVE-2026-41067

GitHub Security Advisory for CVE-2026-41067

GHSA-j687-52p2-xcff · Severity: medium · Ecosystem: npm — Astro: XSS in define:vars via incomplete </script> tag sanitization

Affected software / configurations for CVE-2026-41067

Vendor Product Version Raw CPE
astro astro < 6.1.6 cpe:2.3:a:astro:astro:*:*:*:*:*:node.js:*:*

References for CVE-2026-41067

cvelogic Threat Intelligence