Threat intelligence

Headless Single Sign On <= 1.6 - Unauthenticated PHP Object Injection

CVE-2026-28149 · headless-single-sign-on

Important: Seeing this vulnerability listed does not mean your website is affected. Exposure depends on whether you run Headless Single Sign On at a vulnerable version. How SiteRespond intelligence works

Vulnerability: Headless Single Sign On <= 1.6 - Unauthenticated PHP Object Injection
Affected software: headless-single-sign-on(Plugin)
Affected versions: ≤ 1.6
Authentication: Unauthenticated
Vulnerability type: Other
CVE: CVE-2026-28149
Published: 12 August 2026
CISA KEV: Not listed in CISA KEV at last catalog refresh
Impact: This advisory describes a other issue in the affected software. Review the source advisory and your installed version to assess exposure.
Source: Data imported from Wordfence Intelligence (advisory 254b40a6-d89e-49d3-96b3-9b946d3e05f2). Methodology and redistribution notes

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