CVE-2026-39963: Serendipity has a Host Header Injection allows authentication cookie scoping to attacker-controlled domain in functions_config.inc.php

medium Affects s9y/serendipity. Feed 2026.10.29.1, updated 2026-10-28; published 2026-04-14; advisory modified 2026-04-15.

Serendipity has a Host Header Injection allows authentication cookie scoping to attacker-controlled domain in functions_config.inc.php

Package: s9y/serendipity Composer
Affected versions: <2.6.0
Fixed in: 2.6.0
Severity: medium CVSS 6.9
Exploitation: not on CISA KEV · EPSS 0% (13.0th percentile)
Published: 2026-04-14
Source: osv.dev

References

CWE-565

NVD record s9y/serendipity advisories

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