Defuddle: XSS via unescaped attribute interpolation in site extractors

CISA KEV is observed exploitation evidence. FIRST EPSS is a dated prediction of exploitation in the next 30 days. Missing scores are unknown. This collector requests predictions only for explicit CVE aliases in the public NuGet archive; Microsoft release views retain their existing prediction scope.

No collected risk observation for these identifiers. This does not establish absence of exploitation or a zero probability.

Defuddle cleans up HTML pages. Prior to 0.19.1, site extractors interpolate page-derived image alt and src values, og:image values, and video descriptions into HTML strings without context-appropriate escaping, and buildExtractorResponse() returns this contentHtml without the main pipeline's DOM-based sanitization. The affected paths include src/extractors/x-article.ts, src/extractors/substack.ts, and src/extractors/youtube.ts. A malicious page or attacker-controlled content on a matching domain can inject event-handler attributes or javascript URLs that execute when a victim or downstream application renders the extracted HTML. This issue is fixed in version 0.19.1.

Source published

21 Aug 2026 20:12:53 UTC

Source modified

24 Aug 2026 19:48:53 UTC

Observed here

23 Oct 2026 15:48:27 UTC

Source terms

CVE Program Terms of Use

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: cve-program · CVE Program Terms of Use. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS 3.1 · 8.2 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:L/A:N

Defuddle cleans up HTML pages. Prior to 0.19.1, site extractors interpolate page-derived image alt and src values, og:image values, and video descriptions into HTML strings without context-appropriate escaping, and buildExtractorResponse() returns this contentHtml without the main pipeline's DOM-based sanitization. The affected paths include src/extractors/x-article.ts, src/extractors/substack.ts, and src/extractors/youtube.ts. A malicious page or attacker-controlled content on a matching domain can inject event-handler attributes or javascript URLs that execute when a victim or downstream application renders the extracted HTML. This issue is fixed in version 0.19.1.

Source published

Aug 21, 2026, 8:12:53 PM (timezone not stated)

Source modified

Aug 24, 2026, 7:48:53 PM (timezone not stated)

Observed here

9 Nov 2026 14:10:45 UTC

Source terms

ENISA EUVD · source terms and attribution apply

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This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: euvd · ENISA EUVD · source terms and attribution apply. Source text is retained; field grouping and change labels are provided by ChangeIntel.

EUVD CVSS 3.1 · 8.2 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:L/A:N

Defuddle cleans up HTML pages. Prior to 0.19.1, site extractors interpolate page-derived image alt and src values, og:image values, and video descriptions into HTML strings without context-appropriate escaping, and buildExtractorResponse() returns this contentHtml without the main pipeline's DOM-based sanitization. The affected paths include src/extractors/x-article.ts, src/extractors/substack.ts, and src/extractors/youtube.ts. A malicious page or attacker-controlled content on a matching domain can inject event-handler attributes or javascript URLs that execute when a victim or downstream application renders the extracted HTML. This issue is fixed in version 0.19.1.

Source published

21 Aug 2026 21:17:01 UTC

Source modified

12 Oct 2026 16:10:00 UTC

Observed here

25 Oct 2026 14:19:28 UTC

Source terms

NIST NVD usage terms; underlying source attribution retained

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: nvd · NIST NVD usage terms; underlying source attribution retained. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS 3.1 · [email protected] · Secondary · 8.2 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:L/A:N

## Summary An Improper Neutralization of Input During Web Page Generation issue in the site extractor component allows an attacker-controlled attribute value to be injected into output HTML without escaping. An attacker who crafts a malicious HTML page or controls content on a matching domain can execute arbitrary scripts when a victim processes the page, resulting in Cross-Site Scripting (XSS). This affects defuddle through 0.19.0 and has been patched in version 0.19.1. ## Impact This vulnerability allows for Cross-Site Scripting (XSS) execution without needing to compromise external websites. Affected consumers include: - Obsidian Web Clipper, - web services serving the parsed output directly as HTML, and - any downstream application rendering the unsanitized HTML results ## Patch This issue has been patched in defuddle version 0.19.1. Users are encouraged to update to the latest release.

Source published

21 Aug 2026 20:54:56 UTC

Source modified

21 Aug 2026 21:10:59 UTC

Observed here

24 Oct 2026 13:17:17 UTC

Source terms

GitHub Advisory Database · CC-BY-4.0

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · GitHub Advisory Database · CC-BY-4.0. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS_V3 · CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:L/A:N

Publisher rating · HIGH