CVE-2026-103327 in CryptoCloud Plugin
Summary
by MITRE • 11/03/2026
The CryptoCloud WordPress plugin from 3.0.0 through 3.0.1 does not verify the authenticity of the payment notifications received by its gateway callback, as the integrity check is skipped while the webhook secret is left at its empty default, allowing unauthenticated attackers to mark arbitrary orders as paid or failed without any payment being made.
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 11/03/2026
The vulnerability identified in CryptoCloud WordPress plugin versions 3.0.0 through 3.0.1 represents a critical failure in authentication and integrity verification mechanisms within the payment gateway integration logic. The core technical flaw lies in the handling of webhook callbacks, which are standard HTTP requests sent by third-party payment processors to notify the application of transaction status updates such as success or failure. In this specific implementation, the plugin relies on a webhook secret key to verify that incoming notifications originate from the legitimate payment provider and have not been tampered with during transit. However, the code logic contains a conditional check that skips the integrity verification process when the configured webhook secret remains in its default empty state. This design decision creates a significant security gap because many users fail to update this configuration parameter after initial installation, leaving the system vulnerable by default.
From an operational perspective, this flaw allows unauthenticated attackers to manipulate order statuses without possessing valid credentials or interacting with any legitimate payment gateway. By sending crafted HTTP requests to the callback endpoint, an attacker can arbitrarily mark orders as paid, effectively allowing them to receive goods or services without completing a financial transaction. Alternatively, they could mark orders as failed to disrupt business operations and cause reputational damage. This type of attack exploits the lack of input validation and authentication on sensitive administrative functions, leading directly to integrity violations where the system state is altered by unauthorized actors. The impact extends beyond simple financial loss; it undermines the trustworthiness of the e-commerce platform and can lead to inventory discrepancies and customer service issues due to false order confirmations or cancellations.
This vulnerability aligns with CWE-347, which describes Improper Verification of Cryptographic Signature, as the system fails to ensure that data received from an external source is authentic and has not been altered by unauthorized parties. Furthermore, it maps to MITRE ATT&CK technique T1505.003, specifically Web Service Discovery or exploitation, where attackers interact with exposed services like webhook endpoints to achieve their objectives. The failure also touches upon CWE-287, Improper Authentication, because the system does not adequately verify the identity of the sender before processing sensitive state changes.
To mitigate this risk, administrators must immediately update the CryptoCloud plugin to a patched version that enforces signature verification regardless of configuration states or removes the ability to process callbacks without valid authentication tokens. If an immediate patch is unavailable, site operators should manually configure the webhook secret field with a strong, randomly generated string and ensure it matches the value set in the payment provider's dashboard. Additionally, implementing IP allowlisting for webhook endpoints can provide an additional layer of defense by restricting access to known payment processor addresses, although this alone does not replace the need for cryptographic verification. Regular security audits should include checks for default credentials or empty configuration fields that disable critical security features, ensuring that third-party integrations are hardened against common exploitation patterns associated with insecure direct object references and broken authentication mechanisms.