{"id":"CVE-2026-59728","revision":"533bac11d2cd498d9f181bfa0e7aeb0a","records":[{"revision":"533bac11d2cd498d9f181bfa0e7aeb0a","observedAt":"2026-10-25T14:19:22.811+00:00","statement":{"source":"nvd","id":"CVE-2026-59728","aliases":[],"title":"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-chara…","description":"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.","state":0,"publishedAt":"2026-07-27T21:17:05.7+00:00","modifiedAt":"2026-10-24T13:10:00.147+00:00","affected":[],"metrics":[{"system":"CVSS 3.1 · security-advisories@github.com · Secondary","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N","score":4.3,"severity":"MEDIUM"}],"references":["https://github.com/withastro/astro/commit/fbcfa039dfe3d700b239f595a6c55ee35e45bd06","https://github.com/withastro/astro/pull/17209","https://github.com/withastro/astro/releases/tag/@astrojs/rss@4.0.19","https://github.com/withastro/astro/security/advisories/GHSA-8j5q-mfj2-5q9q"],"sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-59728","license":"NIST NVD usage terms; underlying source attribution retained","enrichment":{"sourceStatus":"Deferred","weaknesses":["CWE-91"],"productCriteria":[],"sourceDates":{"published":"2026-07-27T21:17:05.700","lastModified":"2026-10-24T13:10:00.147"},"relatedAdvisories":[],"note":"NVD analysis and CPE criteria are source context, not proof that a package or your environment is affected. Complete affected data, logical configurations and SSVC are retained in the original JSON."},"key":"nvd:CVE-2026-59728","identifiers":["CVE-2026-59728"]},"retained":false,"historicalAffected":[]}],"coverage":[]}