ThemeREX Hygia theme: PHP object injection via untrusted deserialization
Summary
The Hygia WordPress theme by ThemeREX Group, versions up to and including 1.21.0, deserializes untrusted data. An unauthenticated remote attacker can inject PHP objects, which may allow manipulation of server-side processing and, depending on the classes available on the site, further harmful actions on the server. The CNA rates the issue as critical (CVSS 9.8), and Patchstack expects mass exploitation attempts.
Affected
- Hygia theme for WordPress, versions from n/a through 1.21.0
- Lower bound of the affected range: Unknown.
Fixed in
- Unknown. No patched version has been confirmed by the vendor or the sources reviewed.
- Version 1.24.0 is listed on the ThemeREX page, but it is not confirmed to contain the fix.
Workaround
- No vendor workaround found.
- Patchstack may offer a virtual patch (mitigation rule); ask your hosting provider or WAF vendor whether one is available.
Exploitation
- CISA SSVC: exploitation none, automatable yes, technical impact total.
- Patchstack expects exploitation; EPSS about 0.003; not listed in CISA KEV at the time of review.
- No public proof-of-concept confirmed.
- Unauthenticated and network-reachable, no user interaction required.
Our recommendation
- Check whether any Hygia installation is version 1.21.0 or older and treat it as vulnerable.
- Update to a release verified as fixed; if none is confirmed, apply a virtual patch via your hosting provider or WAF.
- Take a full backup and review admin accounts and recently modified files for signs of compromise.
- Restrict access to admin and sensitive endpoints where feasible.
- Monitor web server logs for suspicious requests.
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- Patchstack advisory: WordPress Hygia theme <= 1.21.0 PHP Object Injection patchstack.com
- Vulners CVE record CVE-2026-93937 vulners.com
- VulDB CVE-2026-93937 vuldb.com
- ThemeREX Hygia product page themerex.net
- ThemeREX documentation education.themerex.net
- Strix AI CVE-2026-93937 www.strix.ai
Researched and written up in English and German by an AI (Claude by Anthropic) based on NVD, CISA, EPSS and the sources listed. The vendor information is authoritative. Researched on 30 Oct 2026, 19:48.
Original description (NVD)
Deserialization of Untrusted Data vulnerability in ThemeREX Group Hygia hygia allows Object Injection.This issue affects Hygia: from n/a through 1.21.0.
Sources
The tracker combines official, freely usable data sources – updated continuously:
- NVD (NIST) – CVEs, rating (CVSS), affected products
- CISA KEV – vulnerabilities confirmed by CISA as actively exploited
- CISA Vulnrichment – CISA assessment (SSVC) in the official CVE record
- FIRST EPSS – probability of exploitation
- Microsoft MSRC – Patch Tuesday: vulnerabilities, severity, updates
- PoC-in-GitHub – public proof-of-concept repositories
- Metasploit (Rapid7) – modules of the Metasploit Framework
- Exploit-DB (OffSec) – archive of public exploits (links only)
- Patch days: official vendor pages (linked per vendor) (Vendor patch days)
This product uses data from the NVD API but is not endorsed or certified by the NVD. EPSS data © FIRST.org.
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