CVE-2026-104732 — Advanced IP Blocker <= 8.13.13 - Unauthenticated Authentication Bypass via Missing Step-1 Binding to 2FA Login Handler
The Advanced IP Blocker plugin for WordPress is vulnerable to Authentication Bypass in all versions up to, and including, 8.13.13 The vulnerability exists because `handle_login_action()` performs no server-side check — via transient, session marker, or equivalent — that a requester completed step-1 password authentication before processing a step-2 TOTP submission for the POSTed `user_id`; compounding this, an error branch in the function unconditionally mints a fresh `advaipbl-2fa-interim-{user_id}` nonce and delivers it in a `Location` header to any unauthenticated caller, after which `display_2fa_login_form_step_2()` renders a valid `advaipbl-2fa-verify-{user_id}` nonce in HTML — both nonces computed against a fixed `uid=0` empty-session context and therefore fully reusable by the attacker across subsequent requests. This makes it possible for unauthenticated attackers to bypass authentication entirely for any 2FA-enabled account, including administrators, by brute-forcing an unthrottled 6-digit TOTP code (no attempt counter, no account lockout, and no `wp_login_failed` firing) and receiving a fully authenticated session cookie via `wp_set_auth_cookie` without ever supplying the account password, resulting in complete site takeover. Exploitation requires only a known `user_id` for an account that has the plugin's 2FA feature enabled.
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- EPSS 0.5% (30-day exploitation probability)+6
- Technical severity (critical)+10
- Automatable exploitation (SSVC)+3
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
CISA SSVC assessment CISA
Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Identify exposed assets running the affected vendor/product/version combinations (IniLerm Advanced IP Blocker).
- The attack is network-based and needs no privileges: restrict exposure (ACLs, VPN, WAF) until patched.
- No fix documented in the sources: reduce exposure and monitor the vendor advisory.
- Search available logs for exploit probes matching the vulnerability class (authentication), errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
| Vendor | Product | Versions | Status | Source |
|---|---|---|---|---|
| IniLerm | Advanced IP Blocker | ≤ 8.13.13 | Vulnerable | CVE Program (cve.org) e CISA ADP |
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
Every base score collected
Sources score independently and may disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Scored by |
|---|---|---|---|---|---|
| 9.8 | CVSS 3.1 | Critical | 3.9 | 5.9 | security@wordfence.com via NIST National Vulnerability Database |
| 9.8 | CVSS 3.1 | Critical | — | — | Wordfence via CVE Program (cve.org) e CISA ADP |
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H (score shown at the top: security@wordfence.com) Weakness MITRE
Weakness class according to MITRE’s CWE catalog.
EPSS over time FIRST
Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 0.47%
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
- Review authentication logs: logins without MFA, anomalous sessions and recently created accounts.
Timeline
What happened to this CVE, newest first.
- 2026
- Affected products added · inilerm/advanced ip blocker
- SSVC assessment updated
- Record published
- CVSS changed · 9.8
- Source status changed · → Deferred
- Record created in this database
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 1× Official description updated · Oct 13, 2026 – Oct 13, 2026
References
7 on the record
- plugins.trac.wordpress.org/browser/advanced-ip-blocker/tags/8.13.13/includes/class-advaipbl-main
- plugins.trac.wordpress.org/browser/advanced-ip-blocker/tags/8.13.13/includes/class-advaipbl-main
- www.wordfence.com/threat-intel/vulnerabilities/id/d080845b-6814-4b10-a3ab-1f5aa1d09132
- plugins.trac.wordpress.org/changeset/3725139/advanced-ip-blocker/trunk/includes/class-advaipbl-m
- plugins.trac.wordpress.org/browser/advanced-ip-blocker/tags/8.13.13/includes/class-advaipbl-main
- plugins.trac.wordpress.org/browser/advanced-ip-blocker/tags/8.13.13/includes/class-advaipbl-main
- plugins.trac.wordpress.org/browser/advanced-ip-blocker/tags/8.13.13/includes/class-advaipbl-2fa-
Elsewhere on this site
Related CVEs (same products)
- High CVE-2026-42739 WordPress Advanced IP Blocker plugin <= 8.10.7 - Cross Site Scripting (XSS) vulnerability May 27, 2026
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No fixed version, patch or mitigation documented.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2026-104732 is "Advanced IP Blocker <= 8.13.13 - Unauthenticated Authentication Bypass via Missing Step-1 Binding to 2FA Login Handler", rated Critical. It affects Advanced IP Blocker (IniLerm); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 9.8 describes technical severity. EPSS 0.47% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
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