Impact The vulnerability could potentially allow a malicious actor to gain control over the destination URL of the HttpClient used in the API classes. For applications using the SDK, requests to unexpected resources on local networks or to the internet could be made which could lead to information disclosure.

Patches Versions of TrueLayer.Client v1.6.0 and later are not affected.

Workarounds The issue can be mitigated by having strict egress rules limiting the destinations to which requests can be made, and applying strict validation to any user input passed to the TrueLayer.Client library.

CVE-2026-103831: Insecure deserialization vulnerability in the Psr16CacheAdapter component of the TrueLayer Magento 2 Plugin, due to the use of PHP's native unserialize() function without restrictions on the classes allowed when retrieving data stored in the cache. An attacker who already has the ability to write manipulated data to the cache backend used by Magento—such as Redis or Memcached—could inject specially crafted PHP objects and trigger their deserialization, potentially leading to arbitrary code execution via gadget strings available in the application environment. Exploitation therefore requires a prerequisite condition that allows writing to the cache infrastructure, either through access to the local file system or to a cache infrastructure accessible from the Magento environment.