CVE-2026-12281
HIGH 8.1 PoC AVAILABLEThe 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.
Public exploit or PoC code exists. Modeled probability is still low, but the barrier to attack is reduced — watch closely.
Exploitation likelihood
0.2%chance of exploitation in 30 days · 14th percentile
Impact if exploited
8.1CVSS 3.1 · HIGH
- ConfidentialityHigh
- IntegrityHigh
- AvailabilityHigh
What an attacker needs
- ✓Access: Reachable over the network — no local access needed
- ✓Privileges: No account or privileges required
- ✓User interaction: No user interaction needed
- ⚠Complexity: Needs a race window or specific setup
✓ lowers the bar for an attacker · ⚠ raises it
Proof of concept & exploit code
- reference https://wpscan.com/vulnerability/8474eda4-6385-447a-9139-f57c049d1713/
- github-search Search GitHub for public PoC repos
Test against your own equipment
curl -s https://vulnpedia.com/cve/CVE-2026-12281/poc.jsonMachine-readable PoC index for this CVE (for automation).Listed for defensive triage, patch verification, and authorized testing on systems you own. Machine-readable: /cve/CVE-2026-12281/poc.json
Weakness (CWE)
- CWE-287: Improper Authentication
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
All CVSS metrics
- HIGH 8.1 v3.1 · ADP Primary
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H - HIGH 8.1 v3.1 · NVD Secondary
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H