Is CVE-2026-126363 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-126363 being exploited in the wild.

How severe is CVE-2026-126363?

Medium severity, with a CVSS score of 4, published 13 November 2026.

Which products and versions are affected?

Astro @Astrojs/Solid-Js 0.2.0 until 7.1.2; @astrojs/solid-js (npm) >= 0.2.0, <= 7.1.1, SEMVER:introduced=0.2.0,fixed=7.1.2.

Is there a fix for CVE-2026-126363?

Yes. @astrojs/solid-js (npm): upgrade to 7.1.2 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-126363 attacked?

It is attacked over the network.

Am I affected by CVE-2026-126363?

Check whether you run Astro @Astrojs/Solid-Js or @astrojs/solid-js (npm) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-126363: Astro @astrojs/solid-js HTML injection in slot names

Q: Is there a fix for CVE-2026-126363?

Yes. @astrojs/solid-js (npm): upgrade to 7.1.2 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

Q: How is CVE-2026-126363 attacked?

It is attacked over the network.

Q: Am I affected by CVE-2026-126363?

Check whether you run Astro @Astrojs/Solid-Js or @astrojs/solid-js (npm) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-126363 · Severity: medium · CVSS 4 · Published 2026-11-13

Astro is a web framework for building content-driven websites. The @astrojs/solid-js renderer failed to properly escape slot names when rendering components, allowing attackers to inject arbitrary HTML through specially crafted slot names. This could lead to cross-site scripting (XSS) attacks if the application accepts user-controlled slot names and uses hydrated Solid components.

Vendors: Astro, npm.

Quick answers

Is CVE-2026-126363 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-126363 being exploited in the wild.
How severe is CVE-2026-126363?: Medium severity, with a CVSS score of 4, published 13 November 2026.
Which products and versions are affected?: Astro @Astrojs/Solid-Js 0.2.0 until 7.1.2; @astrojs/solid-js (npm) >= 0.2.0, <= 7.1.1, SEMVER:introduced=0.2.0,fixed=7.1.2.
Is there a fix for CVE-2026-126363?: Yes. @astrojs/solid-js (npm): upgrade to 7.1.2 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-126363 attacked?: It is attacked over the network.
Am I affected by CVE-2026-126363?: Check whether you run Astro @Astrojs/Solid-Js or @astrojs/solid-js (npm) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

@astrojs/solid-js (npm): upgrade to 7.1.2 or later
```
npm install @astrojs/solid-js@7.1.2
```

Technical details

The @astrojs/solid-js renderer inserted slot names directly into the astro-slot wrapper's name attribute without HTML escaping, allowing a quote character in the slot name to break out of the attribute and inject active HTML elements. Exploitation requires a hydrated Solid component using a client:* directive that dynamically accesses an attacker-controlled slot property; components that do not render the malicious slot output only escaped fallback content. The vulnerability is fixed by escaping slot names before insertion into HTML attributes.

Affected products

Astro @astrojs/solid-js 0.2.0 until 7.1.2

Identifiers

CVE-2026-126363
GHSA-jmv2-qgxf-f995

Timeline

2026-11-13: disclosed
2026-10-28: patched

References

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