Attack Vectors

MailArchiver (WordPress plugin slug: mailarchiver) is affected by CVE-2026-2831, a Medium severity SQL Injection issue (CVSS 4.9, vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N).

This vulnerability can be exploited by an authenticated user with Administrator-level access (or higher) by supplying a crafted value in the logid parameter. While that prerequisite reduces exposure to random internet scanning, it increases the importance of insider-risk scenarios and compromised admin accounts (for example, via credential reuse, phishing, or shared admin logins).

Security Weakness

MailArchiver versions up to and including 4.5.0 are vulnerable because the plugin does not sufficiently escape the user-supplied logid value and does not adequately prepare the related database query. As a result, an attacker with the required access can append SQL into an existing query to extract sensitive information from the WordPress database.

Vendor guidance indicates this is addressed in MailArchiver 4.5.1 (or newer). Reference: CVE-2026-2831 record and the original advisory source at Wordfence Threat Intel.

Technical or Business Impacts

The primary risk highlighted by the CVSS scoring is confidentiality impact (C:H). In business terms, that can translate into exposure of stored data in the WordPress database (for example, operational records and other information your site relies on), creating potential privacy, contractual, and compliance concerns depending on what your site stores and who has access.

Because exploitation requires Administrator-level access, leadership teams should treat this as a control-failure amplifier: if an admin account is compromised, this weakness can make data access and discovery easier. This can increase breach response costs, reporting obligations, and reputational damage—especially if the WordPress instance supports customer communications or other regulated workflows.

Recommended action: Update MailArchiver to version 4.5.1 (or a newer patched release) and review who has Administrator access. In parallel, consider tightening admin privileges, enforcing strong authentication policies, and monitoring for unusual administrator activity that could indicate account compromise.

Similar attacks (real-world examples): SQL injection has been used in high-profile breaches such as the TalkTalk 2015 cyberattack and the Heartland Payment Systems data breach.