Is This vulnerability exploited in the wild?

No. Junglewise Threat Intelligence has no report of This vulnerability being exploited in the wild.

How severe is This vulnerability?

Low severity, with a CVSS score of 3.1, published 8 September 2026.

Which products and versions are affected?

astro (npm) SEMVER:introduced=0,fixed=7.2.8.

Is there a fix for This vulnerability?

Yes. astro (npm): upgrade to 7.2.8 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is This vulnerability attacked?

It is attacked over the network.

Check whether you run astro (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.

Astro remote code execution via AVIF image processing

Severity: low · CVSS 3.1 · Published 2026-09-08

Astro, a popular web framework for building content-driven websites, contains a remote code execution vulnerability in its default image optimization service. An attacker who can upload or cause the server to process a specially crafted AVIF image file can execute arbitrary code on the server. This affects any Astro project that processes untrusted images, potentially leading to complete system compromise and data theft.

Technologies: astro (npm). Vendors: npm.

Quick answers

Is This vulnerability exploited in the wild?: No. Junglewise Threat Intelligence has no report of This vulnerability being exploited in the wild.
How severe is This vulnerability?: Low severity, with a CVSS score of 3.1, published 8 September 2026.
Which products and versions are affected?: astro (npm) SEMVER:introduced=0,fixed=7.2.8.
Is there a fix for This vulnerability?: Yes. astro (npm): upgrade to 7.2.8 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is This vulnerability attacked?: It is attacked over the network.
Am I affected?: Check whether you run astro (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

astro (npm): upgrade to 7.2.8 or later
```
npm install astro@7.2.8
```

Technical details

The vulnerability is a heap buffer overflow (CWE-787 / CWE-125) in libheif's scale_nearest_neighbor() function, triggered by a chain of four behaviors in HEIF/AVIF image processing. A crafted AVIF file with nested iden (identity-derivation) and auxl (auxiliary) item references causes duplicate Alpha planes in the decoded image to be created with different bit depths (8-bit and 10-bit). The scaler allocates a destination Alpha buffer using only the first plane's bit depth (8-bit), then iterates over all source planes. When writing a 10-bit Alpha plane using uint16_t pointers into an 8-bit allocation, it writes twice as many bytes as allocated, causing a controlled overflow. The attack requires the application to process an untrusted AVIF image—no authentication or special API options are needed. Astro versions prior to 7.2.8 are affected through their dependency on vulnerable versions of Sharp. The fix was released in Astro 7.2.8, which requires Sharp 0.35.4 or later.

Affected products

The Astro Project Astro < 7.2.8

Timeline

2026-09-08: disclosed: GHSA-26w7-cxv4-gfx2 published
2026-08-26: patched: Astro 7.2.8 released with Sharp 0.35.4

References

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