Untrusted Deserialization in PrestaShop ps_facetedsearch <=4.0.4 => RCE
CVE-2026-54159 Published on July 17, 2026
ps_facetedsearch: PHP Object Injection in faceted search cache allows unauthenticated RCE
PrestaShop ps_facetedsearch is a module that adds layered navigation filters. From 3.0.0 until 4.0.4, the ps_facetedsearch module rebuilds selected search filters from the request URL, and the value of a slider filter, price or weight, is taken from the URL without sufficient validation and stored in an internal filter-block cache where it is serialized and later read back with a raw native unserialize() in src/Filters/Block.php. By crafting that value, an unauthenticated attacker can smuggle a malicious serialized PHP object into the cache, and when it is deserialized, a gadget chain writes an arbitrary PHP file inside the modules/ps_facetedsearch/ directory, which is then used as a webshell to run commands on the server. This issue is fixed in version 4.0.4.
Vulnerability Analysis
CVE-2026-54159 can be exploited with network access, and does not require authorization privileges or user interaction. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to be critical as this vulnerability has a high impact to the confidentiality, integrity and availability of this component.
Weakness Type
What is an Injection Vulnerability?
The software constructs all or part of a command, data structure, or record using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify how it is parsed or interpreted when it is sent to a downstream component. Software has certain assumptions about what constitutes data and control respectively. It is the lack of verification of these assumptions for user-controlled input that leads to injection problems. Injection problems encompass a wide variety of issues -- all mitigated in very different ways and usually attempted in order to alter the control flow of the process. For this reason, the most effective way to discuss these weaknesses is to note the distinct features which classify them as injection weaknesses. The most important issue to note is that all injection problems share one thing in common -- i.e., they allow for the injection of control plane data into the user-controlled data plane. This means that the execution of the process may be altered by sending code in through legitimate data channels, using no other mechanism. While buffer overflows, and many other flaws, involve the use of some further issue to gain execution, injection problems need only for the data to be parsed. The most classic instantiations of this category of weakness are SQL injection and format string vulnerabilities.
CVE-2026-54159 has been classified to as an Injection vulnerability or weakness.