CVE-2026-86205
Last modified
CVE-2026-86205 is a medium-severity vulnerability rated 5.4/10 on the CVSS scale. 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.. EPSS estimates a 0.20% chance of exploitation in the next 30 days.
Description
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.
Metrics
Weakness Enumeration
Affected Software
Source: CNA advisory (CVE.org). NVD analysis pending.
| Vendor | Product | Versions |
|---|---|---|
| h3js | h3 | >= 2.0.1-rc.17, < 2.0.1-rc.18 |
References
Timeline
- Published
- Last Modified
- Status
- Awaiting Analysis
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