AxiomThemes Kicker: Unauthenticated PHP Object Injection in WordPress theme
Summary
The WordPress theme Kicker in versions up to and including 2.2.1 contains an unauthenticated PHP object injection flaw (CWE-502). An attacker can send crafted serialized data over the network without logging in, which may allow manipulation of server-side processing, denial of service or, depending on other installed code, code execution. Patchstack and NVD rate the issue critical (CVSS 9.8), but no confirmed fixed version, known exploitation or public proof of concept was found at the time of writing.
Affected
- Kicker WordPress theme, versions up to and including 2.2.1
- Versions before 2.2.1 are included in the affected range according to the CVE record
Fixed in
- Unknown. No vendor-confirmed fixed version was found.
- Version 2.2.2 (changelog dated 21.05.2026) lists a fix for a potential object injection during unserialize, but it does not reference this CVE and has not been confirmed as the fix.
Workaround
- Deactivate and delete the Kicker theme if it is not needed.
- No vendor-specific or WAF-based workaround was identified.
- Patchstack reports a mitigation rule that blocks attacks until an official patch is available; this requires a Patchstack subscription.
Exploitation
- No evidence of in-the-wild exploitation. CISA SSVC lists Exploitation: none, Automatable: yes, Technical Impact: total.
- No public proof of concept found.
- Unauthenticated and network-reachable, with low attack complexity according to the CVSS vector.
Our recommendation
- Identify all WordPress sites using Kicker, including agency-managed and staging sites.
- Check the installed version; treat 2.2.1 or earlier, or an unknown version, as vulnerable.
- If the theme is unused, deactivate and delete it.
- If it is needed, obtain written confirmation of the fixed version from AxiomThemes before updating.
- Replace any nulled or unofficial copies with a licensed version.
- Monitor vendor advisories and changes to the CISA exploitation status.
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- Patchstack advisory for Kicker <= 2.2.1 patchstack.com
- OpenCVE CVE-2026-66569 app.opencve.io
- Vulners Rapid7 CVE-2026-66569 vulners.com
- HOL Guard CVE-2026-66569 hol.org
- ThemeForest Kicker (changelog) themeforest.net
- AxiomThemes Kicker documentation kicker.axiomthemes.com
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, 19:24.
Original description (NVD)
Unauthenticated PHP Object Injection in Kicker <= 2.2.1 versions.
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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