CVE-2023-40555

WordPress Flatsome Theme <= 3.17.5 is vulnerable to PHP Object Injection

8.3 High

Deserialization of Untrusted Data vulnerability in UX-themes Flatsome | Multi-Purpose Responsive WooCommerce Theme.This issue affects Flatsome | Multi-Purpose Responsive WooCommerce Theme: from n/a through 3.17.5.

Attack profile

How easy it is to exploit

Attack vector: Network
Complexity: Low
Privileges needed: None
User interaction: None

What an attacker can affect

Confidentiality: Low
Integrity: Low
Availability: Low

Exploit likelihood

0.60%Up 0.6 points since Dec 21, 2023

What each source reports

CVE List Score used 8.3

WordPress Flatsome Theme <= 3.17.5 is vulnerable to PHP Object Injection

Record: CVE-2023-40555
CVSS 3.1: 8.3 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:L
Weakness: CWE-502
Updated: 2026-11-02

EUVDEUVD-2023-45126 8.3

Record: EUVD-2023-45126
CVSS 3.1: 8.3 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:L
Updated: 2026-11-02

GitHub AdvisoriesGHSA-9fmf-6xvc-qw23 8.3

Deserialization of Untrusted Data vulnerability in UX-themes Flatsome | Multi-Purpose Responsive...

Record: GHSA-9fmf-6xvc-qw23
CVSS 3.1: 8.3 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:L
Weakness: CWE-502
Updated: 2026-11-02

NVD 8.3

Record: CVE-2023-40555
CVSS 3.1: 8.3 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:L
CVSS 3.1: 9.8 CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Weakness: CWE-502
Updated: 2026-11-02

Affected products

History

History
Recorded	Changed	Sources
Nov 2, 2026	first indexed	CVE List, EUVD, GitHub Advisories, NVD

Dates are when Every CVE recorded each change. Upstream dates may differ.

In short

CVE-2023-40555 is a high vulnerability (CVSS 8.3) in Ux-themes Flatsome | Multi-purpose Responsive Woocommerce Theme, published December 20, 2023. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.60%, the 49th percentile. No source names a fixed version.