Published: June 2024 <br>CVSS Score: 4.9 (DoS, High Privileges Needed)
What Is CVE-2024-21236?
CVE-2024-21236 is a security vulnerability discovered in the MySQL Server product by Oracle, specifically tied to the InnoDB storage engine. Supported versions 8..39 and earlier, 8.4.2 and earlier, as well as early 9..1 are all affected.
This bug is classified as a Denial of Service (DoS) vulnerability: a high privileged user with simple network access can make MySQL crash or hang repeatedly—something that could devastate apps relying on the database. If you run one of these MySQL versions with untrusted admins, this bug is critical.
Technical Details (Simple Explanation)
The flaw is rooted in how MySQL's InnoDB engine handles certain requests or sequences of commands from privileged users. When abused in particular ways, MySQL gets into a state it can't recover from—a hard crash or endless hang, requiring a manual restart.
CVSS Vector:
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
Exploit Details and Example
According to the Oracle advisory, the vulnerability is easily exploitable with high-level privileges. Let’s look at a simplified exploit workflow:
Attacker gets valid admin access (e.g., DBA or root privileges).
2. Over an authenticated session (possibly remote), attacker issues a crafted SQL sequence that triggers the bug in InnoDB, causing the MySQL instance to hang or crash.
Example Exploit Snippet
The exact technical details are under embargo, but based on MySQL history, similar bugs involve manipulating transactional structures.
For educational purposes, here's a hypothetical sequence that could trigger some InnoDB bugs
-- Log in as root or equivalent
CREATE TABLE a (id INT) ENGINE=InnoDB;
BEGIN;
INSERT INTO a VALUES (1);
-- Simulate complex transactional operation or DDL
ALTER TABLE a ADD COLUMN dummy VARCHAR(10);
-- Immediately roll back/commit and drop table (sequence/desync triggers bug)
ROLLBACK;
DROP TABLE a;
Note:
The above is just a guess at the kind of operation that could trigger a DoS due to InnoDB mishandling internal structures under rapid schema change. The actual exploit for CVE-2024-21236 may differ, but the general approach is similar: using privileged commands to force an InnoDB error that crashes the server.
Patch download:
Oracle Critical Patch Update Advisory - July 2024
References and Further Reading
- Oracle CPUs and Security Advisories
- CVE-2024-21236 in NVD
- MySQL Release Notes
Summary Table
| CVE | Product | Affected Versions | Impact | Exploitability | Requires Privileges | Vector |
|-------------|-----------------|----------------------------|--------------- |----------------|--------------------|-------------------|
| 2024-21236 | Oracle MySQL | ≤8..39, ≤8.4.2, ≤9..1 | DoS (Crash) | Easy | High | Network |
Bottom Line
Don't wait if you manage a MySQL server:
Upgrade now and review admin access policies.
A single misstep by a privileged user could crash your database and take your business offline, thanks to CVE-2024-21236.
*For expert help, see the referenced links or contact your database security provider.*
Timeline
Published on: 10/15/2024 20:15:12 UTC
Last modified on: 10/16/2024 20:41:14 UTC