The Shibboleth WordPress plugin before 2.5.4 does not fail closed when its HTTP header identity mode is enabled without an anti-spoofing key, treating any request that carries identity headers as an authenticated session without verifying them. On a deployment where untrusted client headers reach the application, an unauthenticated attacker can log in with forged identity headers and, when automatic account creation and the default administrator role mapping are enabled, create and sign in as a new administrator. Exploitation requires the non-default HTTP header attribute mode, an empty or absent spoof key, automatic account creation enabled, and a deployment that does not strip untrusted client headers before they reach the application.
CVE-2026-12281
HIGHPre-NVD 8.1Trending — 4 sources updated this week
8.1
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
- High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 0%CVSS: 8.1Exploit: NoneExposed: 0
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 8.1
- EG Score
- 0.0(none)
- EPSS
- 4.6%
- KEV
- Not listed
Published
July 15, 2026
Last Modified
July 15, 2026
Advisory Details (1)
Auto-updated Jul 15, 2026🔬 Proof of concept available. No patch confirmed yet.
generic🟡 PoC Available
Shibboleth < 2.5.4 – Unauthenticated Administrator Account Creation via Identity Header Spoofing | CVE 2026-12281 | Plugin Vulnerabilities
https://wpscan.com/vulnerability/8474eda4-6385-447a-9139-f57c049d1713/Vendor Advisories for CVE-2026-12281(1)
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 5× in last 7d / 5× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
- 2026-07-15 16:57 UTCEPSS rescore
- 2026-07-15 10:44 UTCMITRE cvelistV5CVSS v3 → 8.1 · severity → HIGH
- 2026-07-15 06:20 UTCNVD update
- 2026-07-15 06:05 UTCEG score recompute
- 2026-07-15 06:04 UTCMITRE cvelistV5first tracked
Related CVEs(same CWE)
Frequently asked(5)
What is CVE-2026-12281?
CVE-2026-12281 is a high vulnerability published on July 15, 2026. The Shibboleth WordPress plugin before 2.5.4 does not fail closed when its HTTP header identity mode is enabled without an anti-spoofing key, treating any request that carries identity headers as an authenticated session without verifying them. On a deployment where untrusted client headers reach…
When was CVE-2026-12281 disclosed?
CVE-2026-12281 was first published in the National Vulnerability Database on July 15, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-12281 actively exploited?
CVE-2026-12281 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 4.6% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-12281?
CVE-2026-12281 has a CVSS v3.1 base score of 8.1 (CISA-ADP / Vulnrichment enrichment; NVD's own analysis pending). EchelonGraph synthesises NVD + CISA KEV + FIRST EPSS + GHSA into a combined EG score of 0.0.
How do I remediate CVE-2026-12281?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-12281, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.
Dependency Blast Radius
Explore the affected products and dependency analysis for CVE-2026-12281
Is Your Infrastructure Affected by CVE-2026-12281?
EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.