CVE-2026-40755: WordPress TechLink theme <= 1.3 - PHP Object Injection vulnerability

Synopsis

PHP Object Injection is an unauthenticated vulnerability in the TechLink WordPress theme by Mikado-Themes, affecting all versions up to and including 1.3. It is reachable over the network without any credentials, though exploitation requires meeting specific environmental conditions related to how PHP deserializes attacker-controlled data. Successful exploitation gives an attacker the ability to read sensitive data, tamper with site content, or crash the service, depending on which PHP classes are available in the target environment. HarborGuard is tracking this advisory and will make a patched-image rebuild available as soon as an upstream fix is published.

HarborGuard Coverage

Exploit Conditions

• Network reachabilityRequired

  The attacker must reach the WordPress installation over the network; no local or physical access is needed.

• AuthenticationNot required

  No account or credentials are needed; the injection endpoint is accessible to anonymous users.

• Victim interactionNot required

  The attacker does not need any action from a site user or administrator to trigger the vulnerability.

• Attack complexityDetail

  Exploitation is rated High complexity, meaning the attacker must satisfy specific environmental conditions such as the presence of a suitable PHP class chain (a gadget chain) in the application before the injection can be weaponized.

Blast Radius

• A successful attacker can read sensitive data stored on the server, including credentials, session tokens, or configuration files, depending on available PHP gadget chains.
• An attacker can modify persisted site content, database records, or configuration files if a suitable write-capable gadget chain exists.
• The attacker can crash or destabilize the WordPress process, causing a denial of service for site visitors.
• Full server-side code execution is possible if a gadget chain supporting arbitrary command invocation is present in the PHP environment.