Cross-site Scripting (XSS) Affecting langfuse-3 package, versions <3.163.0-r0


Severity

Recommended
0.0
medium
0
10

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Threat Intelligence

EPSS
0.19% (9th percentile)

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  • Snyk IDSNYK-CHAINGUARDLATEST-LANGFUSE3-15952015
  • published9 Apr 2026
  • disclosed20 Feb 2026

Introduced: 20 Feb 2026

CVE-2026-27121  (opens in a new tab)
CWE-79  (opens in a new tab)

How to fix?

Upgrade Chainguard langfuse-3 to version 3.163.0-r0 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream langfuse-3 package and not the langfuse-3 package as distributed by Chainguard. See How to fix? for Chainguard relevant fixed versions and status.

svelte performance oriented web framework. Versions of svelte prior to 5.51.5 are vulnerable to cross-site scripting (XSS) during server-side rendering. When using spread syntax to render attributes from untrusted data, event handler properties are included in the rendered HTML output. If an application spreads user-controlled or external data as element attributes, an attacker can inject malicious event handlers that execute in victims' browsers. This vulnerability is fixed in 5.51.5.

CVSS Base Scores

version 3.1