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CVE-2026-59728 (GCVE-0-2026-59728)

Vulnerability from cvelistv5 – Published: 2026-07-27 19:54 – Updated: 2026-07-28 14:27
VLAI
Title
@astrojs/rss: XML Injection via Unescaped RSS Feed Fields
Summary
Astro is a web framework for content-driven websites. In versions 1.0.0 through 4.0.18, the source.title and enclosure.type item fields in packages/astro-rss/src/index.ts are interpolated directly into XML template strings without XML-character escaping before being parsed by fast-xml-parser. Both fields are validated only as z.string(), placing no restriction on XML special characters. An attacker who controls these values can inject arbitrary XML into the generated RSS feed: a value containing " can break out of an attribute (as with enclosure.type), and a value containing </source> can close an element early and inject additional nodes (as with source.title). This corrupts feed structure, injects false metadata (for example, a fake <link> pointing to a malicious URL), and can cause feed readers to misparse or display attacker-controlled content. In SSR mode (output: 'server'), the poisoned feed is served on every request to all subscribers. This issue has been fixed in version 4.0.19.
Severity
4.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-28 14:27 UTC
CWE
  • CWE-91 - XML Injection (aka Blind XPath Injection)
Assigner
References
Impacted products
Vendor Product Version CPE status
withastro astro Affected: >= 1.0.0, < 4.0.19
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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