VillaTheme AFFI: Object Injection via unsafe deserialization
Summary
The WordPress plugin AFFI – Affiliate Marketing for WooCommerce up to and including version 1.0.10 deserializes untrusted data, which allows PHP Object Injection. According to the CNA, an unauthenticated attacker can exploit this over the network with low complexity and no user interaction, which may allow manipulation of server-side processing and high impact on confidentiality, integrity and availability. The vendor changelog indicates that the fix in version 1.0.11 replaces PHP serialization with signed JSON for referral cookies.
Affected
- AFFI – Affiliate Marketing for WooCommerce (VillaTheme), all versions up to and including 1.0.10
- Affected range per one aggregator: versions below 1.0.11
Fixed in
- Version 1.0.11 or later (vendor changelog dated 2026.10.08)
Workaround
- None found. Updating the plugin is the only source-reported remedy.
- Unknown whether disabling the plugin or blocking its endpoints is a viable interim measure.
Exploitation
- CISA SSVC: Exploitation none, Automatable yes, Technical Impact total.
- No known exploitation found at the time of writing.
- Not listed in CISA KEV. EPSS 0.00328.
- No public proof of concept found; this does not prove that none exists.
Our recommendation
- Inventory all WordPress sites with AFFI installed and record the version.
- Update to version 1.0.11 or later, or remove the plugin if it is not used.
- Check internet-facing WooCommerce sites for unexpected access and review logs for unusual requests to the plugin.
- Re-check the NVD and Patchstack entries, as the NVD status may have changed.
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- Patchstack advisory CVE-2026-104398 patchstack.com
- WordPress.org plugin listing (changelog) wordpress.org
- OpenCVE CVE-2026-104398 app.opencve.io
- Rapid7 via Vulners CVE-2026-104398 vulners.com
- HOL Guard CVE-2026-104398 hol.org
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, 19:45.
Original description (NVD)
Deserialization of Untrusted Data vulnerability in VillaTheme AFFI – Affiliate Marketing for WooCommerce affi-affiliate-marketing-for-woo allows Object Injection.This issue affects AFFI – Affiliate Marketing for WooCommerce: from n/a through 1.0.10.
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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