HotLock WordPress theme: PHP Object Injection via untrusted data deserialization
Summary
The HotLock WordPress theme by ThemeREX Group, up to and including version 1.3.9, contains a deserialization flaw that allows PHP object injection. An unauthenticated remote attacker can manipulate how the website processes data and run harmful actions on the server. No official fix is available yet, so the theme remains exposed.
Affected
- ThemeREX Group HotLock WordPress theme, versions from n/a through 1.3.9
Fixed in
Unknown. Patchstack lists no official patch available.
Workaround
- Patchstack reports a mitigation rule that blocks attacks until an official patch is available (Patchstack's own guidance).
- Replace the theme with a maintained alternative, or deactivate it and take the site offline until this is done.
- Use a WAF or virtual patching as interim protection.
Exploitation
- Known exploited: not confirmed; the sources do not list it as known exploited.
- Patchstack expects exploitation, which is a forecast and not observed activity.
- Public proof of concept: none found in the research (no dedicated exploit database check was performed).
- EPSS: low (0.00313 to 0.00564 on two snapshots).
- CISA SSVC: Exploitation none, automatable yes, technical impact total.
Our recommendation
- Check whether any WordPress site uses the HotLock theme, including staging sites.
- Replace the theme with a maintained one, or deactivate it, as soon as possible.
- Apply virtual patching or a WAF rule until a replacement is in place.
- Check for signs of compromise: unknown admin users, unexpected PHP files in uploads, changed theme files.
- Do not install copies from unofficial or nulled download sites.
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- Patchstack: PHP Object Injection in WordPress HotLock Theme patchstack.com
- HOL Guard: CVE-2026-112851 hol.org
- Vulners: NVD CVE-2026-112851 vulners.com
- Vulners: EUVD-2026-108950 vulners.com
- Vulners: PT-2026-122071 vulners.com
- Strix AI: CVE-2026-112851 www.strix.ai
- ionix.io threat center www.ionix.io
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, 16:52.
Original description (NVD)
Deserialization of Untrusted Data vulnerability in ThemeREX Group HotLock hotlock allows Object Injection.This issue affects HotLock: from n/a through 1.3.9.
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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