Security Brief: CVE-2026-19949 All-in-One WP Migration Flaw Can Lead to WordPress Site Takeover
https://vulnify.app/blog/security-brief-cve-2026-19949-all-in-one-wp-migration-sqli-rce

CVE-2026-19949 is a high-severity second-order SQL injection vulnerability affecting All-in-One WP Migration and Backup through version 7.109. An unauthenticated attacker can plant malicious database content that is triggered during a later backup restoration, potentially exposing the plugin's secret import key and creating a path to remote code execution and complete WordPress site takeover.

What happened CVE-2026-19949 is a high-severity vulnerability affecting the All-in-One WP Migration and Backup plugin for WordPress, one of the most widely installed WordPress backup and migration tools. The plugin has more than five million active installations and is commonly used to export, back up, restore, clone, and migrate complete WordPress websites, including databases, media, themes, plugins, and configuration data. The vulnerability affects all versions through 7.109 and is fixed in version 7.110, released by developer ServMask on August 20, 2026. Security researcher Jack Taylor discovered the flaw and reported it through the Wordfence Bug Bounty Program in August. CVE-2026-19949 is classified as a second-order SQL injection vulnerability under CWE-89 and carries a CVSS 3.1 score of 8.8, rated High. Successful exploitation can eventually expose sensitive information from the WordPress database, disclose a secret key used by All-in-One WP Migration, and provide a route to importing attacker-controlled backup content that can result in remote code execution. The vulnerability is unusual because the malicious database content does not necessarily execute when the attacker initially submits it. Instead, attacker-controlled data can remain stored inside WordPress until a site administrator later performs a normal export and restore or import operation. That administrative action causes the vulnerable migration code to process the stored data, at which point the SQL injection can become active. How second-order SQL injection works Many SQL injection vulnerabilities occur immediately. An attacker submits crafted input, the application incorrectly inserts that input into a database query, and the malicious SQL is processed during the same request. Second-order SQL injection works differently. The application initially stores attacker-controlled input without executing it as SQL. At some later point, another application function retrieves the stored value and constructs a new SQL query without handling it safely. The data that appeared harmless when first stored can then become executable SQL. A simplified second-order attack pattern looks like this: Attacker-controlled input | v Data stored in WordPress database | | No SQL execution yet v Administrator performs later operation | v Stored data processed by vulnerable code | v SQL query constructed incorrectly | v Injected SQL executes This delayed behavior makes second-order SQL injection particularly difficult to identify through basic request filtering. The request containing the original input may not look like the request that eventually triggers the vulnerability, and the time between the two actions can be substantial. How CVE-2026-19949 works The vulnerable code is involved in database processing during an All-in-One WP Migration archive restoration. According to Wordfence's analysis, the issue involves incorrect handling of escaped backslashes and quotation marks while database values are rewritten during the restore process. An unauthenticated attacker can first place specially constructed data into the WordPress database through functionality such as WordPress trackbacks. At this stage, the input remains stored and the attacker has not yet executed SQL through the migration plugin. The important trigger occurs later. When an administrator exports the affected website and subsequently imports or restores the resulting archive, All-in-One WP Migration processes database content as part of rebuilding the site. The vulnerable parsing logic can transform the previously stored data in a way that causes it to become part of an executable SQL query. Conceptually, the attack chain is: Unauthenticated attacker | v Crafted data stored in WordPress | v Payload remains dormant | v Administrator exports and restores site | v Migration plugin processes database | v Second-order SQL injection triggered | v Sensitive database information exposed This administrator action is an important prerequisite. CVE-2026-19949 does not mean that an attacker can simply send one request to every vulnerable website and immediately execute code. The stored payload must later reach the vulnerable restoration process. However, backup, migration, export, and restoration are the core purposes of All-in-One WP Migration. An administrative restore is therefore not an unusual or unrelated activity. It is exactly the type of operation administrators install the plugin to perform. From SQL injection to remote code execution The SQL injection itself is only one stage of the reported attack chain. The more serious consequence comes from accessing a sensitive All-in-One WP Migration value stored in the WordPress database. The plugin uses a secret value known as ai1wm_secret_key as part of its import functionality. According to Wordfence and BleepingComputer, exploitation of the SQL injection can be used to retrieve this secret and expose it through WordPress content accessible to the attacker. Once an attacker possesses a valid import secret, the security boundary protecting migration operations is weakened. The attacker may then be able to abuse the plugin's import functionality with an attacker-controlled .wpress archive. A .wpress archive can represent an entire WordPress site, including files and database content. Importing attacker-controlled migration data into a live WordPress environment is therefore potentially much more serious than exposing a normal database record. The process can ultimately introduce executable code and lead to remote code execution. The full impact can therefore progress from stored input to SQL injection, secret disclosure, unauthorized migration activity, and finally complete site compromise: Stored attacker input | v Second-order SQL injection | v Plugin secret exposed | v Unauthorized import capability | v Attacker-controlled archive | v Remote code execution | v Potential complete WordPress takeover Why it matters for website owners The scale of All-in-One WP Migration makes CVE-2026-19949 significant even though exploitation requires multiple stages. WPScan lists more than five million active installations of the plugin, making it one of the larger WordPress plugin populations affected by a serious vulnerability in 2026. Backup and migration plugins are also unusually sensitive components. They routinely access almost every important part of a WordPress installation, including the database, themes, plugins, uploads, configuration information, and application files. They need this level of access because their purpose is to reconstruct entire websites. If an attacker gains control of that functionality, the consequences can extend far beyond extracting a few database records. Remote code execution may give the attacker access to WordPress database credentials, administrative data, customer information, WooCommerce records, API keys, SMTP credentials, third-party integration secrets, and other information available to the PHP application. An attacker who obtains code execution may also install persistent backdoors, create administrator accounts, modify existing plugins or themes, inject malicious JavaScript, redirect visitors, alter ecommerce pages, distribute malware, or use the compromised hosting environment as infrastructure for additional attacks. The delayed nature of CVE-2026-19949 creates another operational concern. An attacker could potentially plant malicious data before the site is patched, while the actual SQL injection is triggered later when an administrator restores an archive created while the malicious database content was present. Website owners should therefore avoid assuming that upgrading immediately before a planned migration eliminates every concern relating to archives or data prepared while an affected version was installed. Affected versions and fix The published affected range is straightforward: All-in-One WP Migration and Backup 7.109 and earlier: AFFECTED All-in-One WP Migration and Backup 7.110: PATCHED ServMask released version 7.110 on August 20, 2026 after Wordfence disclosed the vulnerability to the developer. Administrators should update to version 7.110 or a newer supported release. Sites using an older version should not delay the update simply because they have no immediate plans to restore a backup. Attackers may be able to place the first stage of the attack into the site's database while the vulnerable version remains active, leaving malicious content that becomes relevant during a later administrative operation. A deactivated vulnerable copy presents less immediate exposure because the vulnerable plugin code is not normally available while disabled. However, leaving outdated plugins installed creates future risk if they are reactivated during troubleshooting, migration, disaster recovery, or staging work. Removing unnecessary vulnerable software is preferable to leaving it dormant indefinitely. What to check on your site Confirm whether All-in-One WP Migration and Backup is installed. Review production, staging, development, archived, and cloned WordPress sites. Check the installed version. Versions through 7.109 are affected. Update to 7.110 or later. Check whether vulnerable versions were previously active. The current version alone does not establish whether malicious input could have been introduced before patching. Review recent migration activity. Identify unexpected exports, imports, archive restorations, or migration operations. Review WordPress trackback activity. Investigate unusual or unexpected trackbacks, particularly on sites where trackbacks are rarely used. Review publicly accessible comments and database content. Investigate unexplained content that could expose application secrets or values related to migration operations. Protect plugin secrets. If there is evidence that ai1wm_secret_key may have been exposed, treat the value as compromised and follow the plugin vendor's supported process for invalidating or regenerating it. Inspect migration archives. Do not restore unexpected or untrusted .wpress files. Verify the origin and integrity of archives used for disaster recovery or migration. Check WordPress administrator accounts. Look for unexplained users, password changes, privilege changes, or newly created administrators. Review files for unauthorized changes. If remote code execution is suspected, compare WordPress core, plugins, themes, and configuration files against known-good versions. Backup security deserves special attention Backup systems are frequently treated as recovery tools rather than part of the active application attack surface. CVE-2026-19949 demonstrates why that distinction can be misleading. A WordPress backup contains highly trusted data. Restoring it can rewrite the database, replace application files, install themes and plugins, modify users, change configuration, and restore executable PHP code. That makes the provenance and integrity of a backup archive important security properties. Organizations should restrict access to migration archives, avoid storing sensitive backups in publicly accessible web directories, and maintain trusted offline or separately protected copies for disaster recovery. Backup files should only be restored from known sources and should not be accepted from unauthenticated users. Administrators should also keep backup plugins patched even when migrations are infrequent. A plugin that is only used every few months can remain exposed to visitors every day if it stays active on the production website. SQL injection is not only about data theft SQL injection is commonly associated with reading usernames, email addresses, password hashes, or other database information. CVE-2026-19949 illustrates how SQL injection can become part of a larger attack chain where the most important stolen value is an application secret. Modern applications store API tokens, signing keys, reset values, integration credentials, and other security-sensitive information alongside ordinary database content. Extracting one such value can unlock an entirely different application feature that was never directly vulnerable to SQL injection. This is why remediation should focus on eliminating the underlying unsafe query construction rather than attempting to block a handful of known SQL strings. Parameterized database operations and correct handling of untrusted input remain the reliable application-level defence against SQL injection. Recommended response The first action for affected sites is to update All-in-One WP Migration and Backup to version 7.110 or later. Where the plugin is not required, removing it reduces unnecessary attack surface. Administrators who used an affected version should also review whether backup exports or restores took place while that version was installed. Particular attention is warranted if unexplained trackbacks, suspicious database content, unexpected migration activity, or unfamiliar archive files are present. If there is evidence that the plugin's secret import key was exposed, administrators should treat the migration authorization mechanism as compromised rather than assuming the site remains protected because the plugin has now been updated. If unauthorized archive imports or server-side code execution are suspected, the investigation should expand beyond the plugin itself. Review administrator accounts, PHP files, themes, plugins, scheduled tasks, WordPress configuration, database content, hosting logs, and credentials available to the WordPress process. Where compromise is confirmed, potentially exposed credentials should be rotated and the affected installation should be rebuilt or cleaned using trusted application files and known-good recovery data. Using Vulnify for WordPress review The Stack Checker can help website owners review publicly detectable WordPress technology and identify sites that require closer plugin and version inspection. This can be particularly useful for organizations managing multiple WordPress properties where forgotten marketing, staging, or legacy installations may still be publicly reachable. Vulnify can support public-surface assessment, but CVE-2026-19949 depends on server-side database processing and an administrator's later migration activity. A public scanner cannot reliably prove whether malicious second-order SQL data exists inside a WordPress database or whether a historical archive contains attacker-controlled content. Direct WordPress administration and server-side review remain necessary. Developers and security teams reviewing SQL injection concepts can also use Vulnify's Injection Payloads reference for controlled security testing and validation against systems they are authorized to assess. Testing should be performed in staging or other approved environments rather than against production systems where database modification could interrupt service. For broader WordPress remediation guidance, the Security Hardening Checklist covers plugin management, updates, administrative controls, exposed functionality, and other practical measures for reducing WordPress risk. Related reading Security Hardening Checklist Stack Checker Conclusion CVE-2026-19949 is not a conventional one-request SQL injection vulnerability. The attacker can place malicious data into WordPress first, while the dangerous database operation occurs later when an administrator performs a normal All-in-One WP Migration export and restore workflow. That additional prerequisite reduces immediate exploitability, but it does not make the flaw insignificant. Backup and restoration are precisely the operations the plugin is designed to perform, and successful exploitation can progress from SQL injection to disclosure of the plugin's secret import key and ultimately remote code execution. All-in-One WP Migration and Backup versions through 7.109 are affected. Version 7.110 contains the fix. With more than five million active installations, administrators should verify their plugin versions rather than assuming automatic updates have already resolved the issue. Update the plugin, review historical migration and trackback activity where appropriate, protect migration secrets, and investigate further if unexpected archives, administrator accounts, file changes, or import operations are discovered. Backup software has privileged access to almost every part of a WordPress site, which makes keeping it patched just as important as maintaining the site's public-facing plugins and themes. Sources : WordPress backup plugin flaw exposes millions of sites to takeover attacks : 5 Million WordPress Sites Affected by SQL Injection Vulnerability in All-in-One WP Migration and Backup