CVE-2026-85590Public exploitNetwork attack vectorHinoki check available

Two-factor downgrade via session-only disable handlers

Published Sep 4, 2026 · Updated Sep 4, 2026

Authentication bypass in phpMyFAQ before 4.1.8 allows remote authenticated users to disable TOTP through the user API. The removeTwofactorConfig() and updateData() handlers accept a session, CSRF token, or form field without verifying a password or current TOTP code. A hijacked session and valid CSRF token are required; disabling TOTP permits later password-only authentication, including for administrator accounts.

CVSS severity7.1
High
EPSS probability0.39%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Authentication bypass in phpMyFAQ before 4.1.8 allows remote authenticated users to disable TOTP through the user API. The removeTwofactorConfig() and updateData() handlers accept a session, CSRF token, or form field without verifying a password or current TOTP code. A hijacked session and valid CSRF token are required; disabling TOTP permits later password-only authentication, including for administrator accounts.

The record

CVE
CVE-2026-85590
Published
Sep 4, 2026
Updated
Sep 4, 2026
Vendor
Thorsten Rinne
Product
phpMyFAQ
Classifications
CWE-308, T1556
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Sep 4, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 4, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <4.1.8

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Thorsten Rinne · phpMyFAQversion=0 <4.1.8

Published CVSS scores

7.1VulnCheck CNACVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-308Use of Single-factor Authentication
T1556Modify Authentication Process

Public exploit references

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Technologies

Your stack

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Your stack

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