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Fencer Vulns
medium 6.4

CVE-2026-23885 json

AlchemyCMS has Authenticated Remote Code Execution (RCE) via eval injection in ResourcesHelper

published 2026-01-19 9 mo ago modified 2026-06-17 4 mo ago also EUVD-2026-3281 , GHSA-2762-657x-v979

cvss
6.4
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.5%
EPSS 0.5% chance of exploitation in 30 days, percentile 41%
public exploits
0
none known

Summary

Alchemy is an open source content management system engine written in Ruby on Rails. Prior to versions 7.4.12 and 8.0.3, 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`. 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. Versions 7.4.12 and 8.0.3 fix the issue by replacing `eval()` with `send()`.

Patch / fix

  • rubygems alchemy_cms 7.4.12, 8.0.3
  • alchemy-cms alchemy_cms 7.4.12, 8.0.3

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
total
Assessed
9 mo ago

Exploit prediction

0.47% chance of exploitation in the next 30 days, higher than 41% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 3.1 6.4 CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H
GitHub 3.1 6.4 CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H
NVD 3.1 9.9 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

Affected packages

ecosystem package affected fixed in
rubygems alchemy_cms
<7.4.12
>=8.0.0.a, <8.0.3
7.4.12
8.0.3

Affected products

  • AlchemyCMS alchemy_cms

Classification

Weakness
  • CWE-95 Improper Neutralization of Directives in Dynamically Evaluated Code

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.