CVE-2026-85588 in phpMyFAQ
Summary
by MITRE • 09/04/2026
phpMyFAQ versions before 4.1.8 include live TOTP shared secrets in plaintext within user data export ZIP files. Attackers obtaining exported archives can extract the TOTP seed and generate valid one-time codes to bypass two-factor authentication.
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Analysis
by VulDB Data Team • 09/04/2026
The vulnerability identified in phpMyFAQ prior to version 4.1.8 represents a critical failure in the handling of sensitive cryptographic material during data export operations. Specifically, when users or administrators initiate an export of their account data into a ZIP archive, the system inadvertently includes the live Time-based One-Time Password shared secrets stored in plaintext within this file. This design flaw effectively neutralizes one of the primary layers of defense against unauthorized access by exposing the foundational seed required to generate valid authentication codes outside of the intended secure context.
From a technical perspective, TOTP relies on a pre-shared secret key that is synchronized between the server and the authenticator application. While this secret must be stored securely during normal operation, typically using strong hashing or encryption at rest, its inclusion in an exported data package violates fundamental security principles regarding sensitive information handling. The export feature, intended for user convenience and data portability, fails to sanitize or exclude high-value credentials such as MFA seeds. Consequently, any individual with access to these exported files can reverse-engineer the TOTP algorithm using standard libraries to produce valid six-digit codes that match those generated by the user's authenticator app in real-time.
The operational impact of this vulnerability is severe, particularly for organizations relying on phpMyFAQ as a knowledge base or internal documentation portal where multi-factor authentication has been enforced. An attacker who gains access to exported user data files can bypass two-factor authentication entirely without needing to compromise passwords or exploit other system flaws. This capability allows for full account takeover, enabling the attacker to read sensitive documents, modify content, and potentially escalate privileges if administrative accounts are compromised. The risk is exacerbated by the fact that export functions are often accessible to regular users who may store these files on less secure local devices or transmit them via insecure channels, increasing the surface area for credential theft.
This flaw aligns with CWE-312, which describes Cleartext Storage of Sensitive Information, as well as CWE-640, Weak Password Recovery Mechanism for Forgotten Passwords if the export is used in recovery flows. In terms of offensive security frameworks, this vulnerability facilitates privilege escalation and credential access under MITRE ATT&CK techniques such as T1539 Steal Web Session Cookie or more broadly T1078 Valid Accounts when combined with other initial access vectors. The exposure of MFA seeds effectively renders the multi-factor authentication control ineffective for any user whose data has been exported, creating a significant gap in identity and access management controls.
Mitigation strategies must prioritize immediate software updates to version 4.1.8 or later where this issue is resolved by excluding TOTP secrets from export archives. For systems that cannot be immediately updated, administrators should enforce strict file permissions on the directories containing user exports to prevent unauthorized reading of these files. Additionally, implementing a mandatory MFA re-enrollment process for all users after patching ensures that any potentially compromised seeds are rotated out and replaced with new, secure values. Security audits should also review other export or backup mechanisms within the application to ensure no other sensitive credentials such as API keys or session tokens are similarly exposed in plaintext formats during data transfer operations.