CVE-2026-29053
📋 TL;DR
Ghost CMS versions 0.7.2 through 6.19.0 contain a vulnerability where malicious themes can execute arbitrary code on the server. This allows attackers with theme upload privileges to gain full control of the Ghost instance. All Ghost installations using vulnerable versions are affected.
💻 Affected Systems
- Ghost CMS
⚠️ Manual Verification Required
This CVE does not have specific version information in our database, so automatic vulnerability detection cannot determine if your system is affected.
Why? The CVE database entry doesn't specify which versions are vulnerable (no version ranges provided by the vendor/NVD).
🔒 Custom verification scripts are available for registered users. Sign up free to download automated test scripts.
- Review the CVE details at NVD
- Check vendor security advisories for your specific version
- Test if the vulnerability is exploitable in your environment
- Consider updating to the latest version as a precaution
⚠️ Risk & Real-World Impact
Worst Case
Complete server compromise leading to data theft, ransomware deployment, lateral movement to other systems, and persistent backdoor installation.
Likely Case
Attacker gains shell access to the Ghost server, steals sensitive data, defaces websites, or uses the server for further attacks.
If Mitigated
With proper theme review processes and limited upload privileges, risk is reduced but not eliminated as legitimate themes could still be compromised.
🎯 Exploit Status
Exploitation requires theme upload privileges. Attackers could compromise legitimate themes or trick users into installing malicious themes.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 6.19.1
Vendor Advisory: https://github.com/TryGhost/Ghost/security/advisories/GHSA-cgc2-rcrh-qr5x
Restart Required: Yes
Instructions:
1. Backup your Ghost instance and database. 2. Update Ghost using npm: 'npm install -g ghost-cli@latest' then 'ghost update'. 3. Verify version is 6.19.1 or higher. 4. Restart Ghost service.
🔧 Temporary Workarounds
Disable theme uploads
allTemporarily disable theme upload functionality to prevent exploitation
Modify Ghost configuration to remove theme upload permissions
Restrict theme sources
allOnly allow themes from trusted, verified sources
Implement allowlist for theme sources in Ghost configuration
🧯 If You Can't Patch
- Implement strict theme review process before installation
- Isolate Ghost instance in network segment with limited outbound access
🔍 How to Verify
Check if Vulnerable:
Check Ghost version: 'ghost version' or check package.json for version number between 0.7.2 and 6.19.0Check Version:
ghost versionVerify Fix Applied:
Confirm version is 6.19.1 or higher: 'ghost version' should show 6.19.1+📡 Detection & Monitoring
Log Indicators:
- Unusual theme uploads from unexpected sources
- Suspicious file operations in theme directories
- Unexpected child process creation
Network Indicators:
- Outbound connections from Ghost server to unknown IPs
- Unusual traffic patterns from Ghost instance
SIEM Query:
source="ghost.log" AND ("theme upload" OR "malicious" OR "exec")