CVE-2026-23885 is a medium-severity (CVSS 6.4) CWE-95 vulnerability in alchemy_cms. A fix is available for alchemy_cms — see the affected versions and patch details below.
AlchemyCMS has Authenticated Remote Code Execution (RCE) via eval injection in ResourcesHelper
Exploitation Status
No confirmed exploitation observed yet
- A successful exploit gives an attacker total control of the affected component, not partial access.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-23885.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2026-23885 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 378,567 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
alchemy_cms💎alchemy_cmsReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects RubyGems packages — download data is not available via public APIs for these ecosystems.
Description
Summary
A vulnerability was discovered during a manual security audit of the AlchemyCMS source code. The application uses the Ruby eval() function to dynamically execute a string provided by the resource_handler.engine_name attribute in Alchemy::ResourcesHelper#resource_url_proxy.
Details
The vulnerability exists in app/helpers/alchemy/resources_helper.rb at line 28. The code explicitly bypasses security linting with # rubocop:disable Security/Eval, indicating that the use of a dangerous function was known but not properly mitigated.
Since engine_name is sourced from module definitions that can be influenced by administrative configurations, it allows an authenticated attacker to escape the Ruby sandbox and execute arbitrary system commands on the host OS.
But, for this attack to be possible local file access to the alchemy project or the source on a remote server is necessary in order to manipulate the module config file, though.
PoC (Proof of Concept)
The following standalone Ruby script demonstrates that the eval sink is directly exploitable:
require 'ostruct'
def resource_url_proxy(resource_handler)
if resource_handler.engine_name && !resource_handler.engine_name.empty?
eval(resource_handler.engine_name)
end
end
# Payload to create a file in /tmp directory
payload = "system('touch /tmp/alchemy_rce_verified'); 'main_app'"
handler = OpenStruct.new(engine_name: payload)
resource_url_proxy(handler)
if File.exist?('/tmp/alchemy_rce_verified')
puts "RCE Verified: Command executed successfully."
end
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 💎RubyGems | alchemy_cms | all versions | 7.4.12bundle update alchemy_cms --conservative |
| 💎RubyGems | alchemy_cms | ≥ 8.0.0.a&&< 8.0.3 | 8.0.3bundle update alchemy_cms --conservative |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for alchemy_cms, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update alchemy_cms to 7.4.12 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-23885 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2026-23885 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2026-23885. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-23885 in your dependencies?
O3 Security finds CVE-2026-23885 across RubyGems dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.