ps_facetedsearch: Improper Neutralization of Special Elements in Output Used by a Downstream Component
CVE-2026-54159 is a critical-severity improper neutralization of special elements in output used by a downstream component vulnerability in ps_facetedsearch from PrestaShop, with a CVSS 3.1 base score of 10.0 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected ps_facetedsearch versions: >= 3.0.0, < 4.0.4. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.75% chance of exploitation within 30 days, higher than 56% of scored CVEs.
Critical severity: a successful attack would have severe impact.
What to do
- Check which version of ps_facetedsearch you run against the affected versions below, and install the vendor's latest release.
- Read the advisory on github.com for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| PrestaShop | ps_facetedsearch | >= 3.0.0, < 4.0.4 | Not stated |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- ChangedThe attack can reach beyond the vulnerable component into other systems.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H. Scored by CNA (github.com).
Official description
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.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Neutralization of Special Elements in Output Used by a Downstream Component
The product 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.
How developers prevent this class of flaw
- Programming languages and supporting technologies might be chosen which are not subject to these issues.
- Utilize an appropriate mix of allowlist and denylist parsing to filter control-plane syntax from all input.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
Recent Improper Neutralization of Special Elements in Output Used by a Downstream Component vulnerabilities
- 7.3 High severity
- 10.0 Critical severity
- 7.3 High severity
- 7.3 High severity
- 7.3 High severity
- 7.3 High severity
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