@astrojs/netlify generates an overly-broad Netlify Image CDN allowlist because remotePatterns.pathname metacharacters are not escaped

published 2026-07-20 3 mo ago modified 2026-10-24 16 d ago also EUVD-2026-57610 , GHSA-hp3v-mfqw-h74c

cvss: 3.7; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.3%; EPSS 0.3% chance of exploitation in 30 days, percentile 19%
public exploits: 0; none known

Astro is a web framework for content-driven websites. Prior to 8.1.2, the Astro Netlify adapter converts each image.remotePatterns entry into a regular expression written to .netlify/v1/config.json under images.remote_images for Netlify's Image CDN allowlist. In packages/integrations/netlify/src/index.ts, remotePatternToRegex() escapes dots in hostname values but interpolates literal pathname values without escaping regular expression metacharacters such as ., +, ?, (, and [, so a restrictive pathname such as /img/v1.0/file also matches metacharacter-adjacent paths, including paths that cross a segment. Netlify enforces the generated regular expression directly and Astro's matchPattern() helper does not revalidate the request, allowing optimization of images on an already-allowed host that the declared pathname was intended to exclude. This issue is fixed in version 8.1.2.

Patch / fix

fixed in 2 links 4

npm @astrojs/netlify 8.1.2
astro @astrojs/netlify 8.1.2

github.com/withastro/astro@ee74c28 commit
github.com/withastro/astro#17018 pull request
github.com/withastro/astro#17368 pull request
github.com/withastro/astro/releases/tag/@astrojs/netlify@8.1.2 release

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: 2 mo ago (2026-08-13)

Exploit prediction

0.27% chance of exploitation in the next 30 days, higher than 19% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	3.7	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N
GitHub	3.1	3.7	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N

Affected packages

ecosystem	package	affected	fixed in
npm	@astrojs/netlify	<8.1.2	8.1.2

Affected products

withastro astro

Classification

Weakness

CWE-185 Incorrect Regular Expression

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.

Summary