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CVE-2026-19423

HIGH 8.1 PoC AVAILABLE

Published 2026-08-28 · Last modified 2026-08-28

The Ultimate Member WordPress plugin before 2.13.0 does not validate a submitted role selection when it cannot resolve the set of roles a profile form permits, and screens the value against the site's registered role names rather than against the form's own allow-list, allowing unauthenticated users who register through the Ultimate Member WordPress plugin before 2.13.0's own form to grant themselves arbitrary capabilities and reach administrator-equivalent access.

EXPLOIT AVAILABLE

Public exploit or PoC code exists. Modeled probability is still low, but the barrier to attack is reduced — watch closely.

Exploitation likelihood

0.1%chance of exploitation in 30 days · 4th percentile

○ In CISA KEV ● Public exploit / PoC

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

Test against your own equipment

curl -s https://vulnpedia.com/cve/CVE-2026-19423/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-2026-19423/poc.json

Affected

Vendors Unknown

Products Ultimate Member

Weakness (CWE)

  • CWE-269: Improper Privilege Management

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

References

Exploits & PoC

Sources: NVD · CVE.org · EPSS