CVE-2024-3431 is a medium severity deserialization flaw (CVSS 4.7) in the EyouCMS 1.6.5 admin backend. The record lists no fix, and says the vendor did not respond to the disclosure. Restrict access to the admin area and review the site for changes.
What's affected
The record lists EyouCMS 1.6.5. The weakness is CWE-502 (deserialization of untrusted data). It is in code behind the backend path /login.php?m=admin&c=Field&a=channel_edit, through the channel_id argument. The CVSS vector in the record says the attack is reached over the network, with low attack complexity, needing high privileges and no user interaction. The score is lower than the word critical in the description suggests, because the vector requires high privileges, so an attacker needs an admin account first.
The description says the attack can be started remotely and that the exploit has been disclosed to the public and may be used. That is a public write-up, not a report of attacks in the wild. The record's KEV flag is false, so CISA's Known Exploited Vulnerabilities catalog did not list it when this record was captured.
The description also says the vendor was contacted early about the disclosure and did not respond in any way. No fixed version is listed. I could not confirm one, so check the project site for a newer release than 1.6.5.
How to check if you're exposed
Start with an inventory. List every place EyouCMS runs in your environment, including test and demo copies that people forget. Note the exact version string on each one and compare it with the versions in the record (1.6.5). For a PHP application that was copied onto a web server, the version is usually in the project folder name, a readme or the admin page footer, so check the files on disk rather than relying on memory.
Because the flaw sits behind the admin login, also ask who holds admin accounts. Remove accounts that are not needed, enforce strong unique passwords, and check the admin login log for sign ins you do not recognise. You can also run a free in-browser dependency scan at gold.safeguard.sh/scan to see which known vulnerabilities touch the open source packages you ship.
Safeguard's reachability analysis helps with the next question, which is whether the vulnerable code is actually called in your application, so you can order the work sensibly.
What to do now
- Move the admin backend behind a VPN or an IP allow list, or block the backend path at the web server for outside visitors.
- Audit admin accounts and remove any you do not need. Reset passwords for the rest.
- Check the site files and the database for changes you did not make, and compare against a clean copy of the release.
- Watch the project site for a release newer than 1.6.5 and read its notes before upgrading.
- Keep tested backups so you can restore if the site is altered.
Why it matters
Deserialization turns stored or transmitted data back into live objects inside the application. When the data comes from a user and the application does not limit what it will rebuild, the user can influence what the program does. The record describes the flaw only at the level of one admin function and one parameter.
The fix belongs in the code: avoid deserializing untrusted input, or use a data format that cannot carry executable behaviour, and restrict the classes that may be rebuilt. Until that exists, the practical defence is to keep the admin backend away from the public internet.
The record's KEV flag is false, so CISA's Known Exploited Vulnerabilities catalog did not list it when this record was captured.
Quick check
The description says critical but the score is medium. Which is right?
Both are in the record. The text uses the word critical, which is VulDB's own wording, while the CVSS 3.1 score of 4.7 is medium because it requires high privileges. Use the score and vector for planning and read the admin access requirement carefully.
Sources
- NVD record data for CVE-2024-3431
- Reference links listed in the record, not fetched for this post: https://terrific-street-3d0.notion.site/EYOUCMS-v1-6-5-RCE-7fe12e91a9b249e88e6ab36446b5ba22, https://vuldb.com/?ctiid.259612, https://vuldb.com/?id.259612
Last reviewed: 19 October 2026.
