How severe is CVE-2026-28148?

CVE-2026-28148 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-28148 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (15th percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2026-28148?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2026-28148 published?

CVE-2026-28148 was published on 2026-08-13 and last updated on 2026-08-14.

CVE-2026-28148

CVE-2026-28148 is a critical-severity vulnerability with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-347.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
EPSS exploit prediction: 0% (15th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-347
Published: 2026-08-13
Last modified: 2026-08-14

Description

Unauthenticated Bypass Vulnerability in Headless Single Sign On <= 1.6 versions.

Frequently asked questions

What is CVE-2026-28148?: Unauthenticated Bypass Vulnerability in Headless Single Sign On <= 1.6 versions.
How severe is CVE-2026-28148?: CVE-2026-28148 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-28148 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (15th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-28148?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2026-28148 published?: CVE-2026-28148 was published on 2026-08-13 and last updated on 2026-08-14.

References

https://patchstack.com/database/wordpress/plugin/headless-single-sign-on/vulnerability/wordpress-headless-single-sign-on-plugin-1-6-bypass-vulnerability-vulnerability?_s_id=cve

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