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CVE-2026-86205

CVE-2026-86205 · h3 before 2.0.1-rc.18 Open Redirect via redirectBack()

This page contains facts from public vulnerability sources. Check the original advisory before updating.

h3 versions before 2.0.1-rc.18 contain an open redirect vulnerability in the redirectBack() utility that fails to sanitize protocol-relative paths in the Referer header pathname. Attackers can craft a same-origin URL with a double-slash path segment that passes origin validation but produces a Location header interpreted by browsers as a protocol-relative redirect to an external domain.

CVSS 5.3 · Medium · EPSS 0.3% · Fix available

Published
Updated

Stack: node

Affected products and versions

  • h3

    Versions
    • ≥ 2.0.1-rc.17, < 2.0.1-rc.18: Affected (semver)
    • 2.0.1-rc.18: Not affected (semver)

    Update to 2.0.1-rc.18

  • h3 npm

    Versions
    • 2.0.1-rc.17
    Affected ranges
    • SEMVER: ≥ 2.0.1-rc.17, < 2.0.1-rc.18

    Update to 2.0.1-rc.18

Original sources

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