ThemeREX Little Birdies WordPress theme: PHP Object Injection
Summary
The Little Birdies WordPress theme up to and including version 1.3.16 contains a deserialization flaw that allows PHP Object Injection. An unauthenticated remote attacker can send crafted data to manipulate how the website processes objects, which may lead to harmful actions on the server. The CNA rates the issue CVSS 9.8 (Critical); no official vendor fix was available at the time of the sources.
Affected
- Little Birdies theme from n/a through 1.3.16 (ThemeREX Group)
Fixed in
- Unknown. Patchstack lists no official patch available. One unreliable aggregator names 1.3.17; this is unverified.
Workaround
- Unknown vendor workaround.
- Deactivate the theme where possible and move to a maintained theme.
- Restrict access to the WordPress admin area and place a web application firewall or virtual patch in front of the site.
- Check for signs of compromise and keep backups.
Exploitation
- Exploited in the wild: not confirmed.
- Public proof of concept: none found.
- Patchstack expects exploitation and rates the issue high priority; this is a forecast, not an observed attack.
- EPSS about 0.3%.
Our recommendation
- Check whether any website uses the Little Birdies theme.
- If it is in use, treat the site as affected until a vendor fix is confirmed, and plan replacement with a maintained theme.
- Add a WAF or virtual patch layer and restrict admin access.
- Check the site for signs of compromise before removing the theme.
- Verify the reported version 1.3.17 with the vendor.
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- Patchstack advisory patchstack.com
- NVD mirror (Vulners) vulners.com
- VulDB vuldb.com
- Threatint cve.threatint.com
- HOL Guard 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, 16:48.
Original description (NVD)
Deserialization of Untrusted Data vulnerability in ThemeREX Group Little Birdies little-birdies allows Object Injection.This issue affects Little Birdies: from n/a through 1.3.16.
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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