Local Information Disclosure Vulnerability in io.netty:netty-codec-http
Description
GHSA-5mcr-gq6c-3hq2 (CVE-2021-21290) contains an insufficient fix for the vulnerability identified.
Impact
When netty's multipart decoders are used local information disclosure can occur via the local system temporary directory if temporary storing uploads on the disk is enabled.
This only impacts applications running on Java version 6 and lower. Additionally, this vulnerability impacts code running on Unix-like systems, and very old versions of Mac OSX and Windows as they all share the system temporary directory between all users.
Vulnerability Details
To fix the vulnerability the code was changed to the following:
@SuppressJava6Requirement(reason = "Guarded by version check")
public static File createTempFile(String prefix, String suffix, File directory) throws IOException {
if (javaVersion() >= 7) {
if (directory == null) {
return Files.createTempFile(prefix, suffix).toFile();
}
return Files.createTempFile(directory.toPath(), prefix, suffix).toFile();
}
if (directory == null) {
return File.createTempFile(prefix, suffix);
}
File file = File.createTempFile(prefix, suffix, directory);
// Try to adjust the perms, if this fails there is not much else we can do...
file.setReadable(false, false);
file.setReadable(true, true);
return file;
}Unfortunately, this logic path was left vulnerable:
if (directory == null) {
return File.createTempFile(prefix, suffix);
}This file is still readable by all local users.
Patches
Update to 4.1.77.Final
Workarounds
Specify your own java.io.tmpdir when you start the JVM or use DefaultHttpDataFactory.setBaseDir(...) to set the directory to something that is only readable by the current user or update to Java 7 or above.
References
- CWE-378: Creation of Temporary File With Insecure Permissions
- CWE-379: Creation of Temporary File in Directory with Insecure Permissions
For more information
If you have any questions or comments about this advisory:
Open an issue in netty
Affected software
Click a technology to see all vulnerabilities affecting it.
| Platform | Package | Vulnerable versions | Fixed in |
|---|---|---|---|
| Java / Kotlin (Maven) | io.netty:netty-codec-http | < 4.1.77.Final | 4.1.77.Final |
References
- https://github.com/netty/netty/security/advisories/GHSA-269q-hmxg-m83q
- https://github.com/netty/netty/security/advisories/GHSA-5mcr-gq6c-3hq2
- https://nvd.nist.gov/vuln/detail/CVE-2022-24823
- https://github.com/netty/netty/commit/185f8b2756a36aaa4f973f1a2a025e7d981823f1
- https://github.com/netty/netty
- https://security.netapp.com/advisory/ntap-20220616-0004
- https://www.oracle.com/security-alerts/cpujul2022.html
- CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N- Weakness (CWE)
CWE-378, CWE-379, CWE-668- Platform
- Java / Kotlin (Maven)
- Package
io.netty:netty-codec-http- Disclosed
- 10.05.2022
- Updated
- 11.10.2026 12:22
Sources and licenses
OSV / GitHub Advisory Database - GHSA-269q-hmxg-m83q - CC BY 4.0
Vulnerability history: io.netty:netty-codec-http
All published vulnerabilities of this package (Java / Kotlin (Maven)), newest first. Shows whether this is a one-off slip or a package that needs watching.
- Total entries
- 24
- First → latest
- 02.2020 08.2026
- Without a fix
- 0
- Exploited in attacks
- 0
Severity breakdown
- Critical 1
- High 6
- Medium 16
- Low 1
Disclosures per year
- 2020: 1
- 2021: 2
- 2022: 2
- 2023: 0
- 2024: 1
- 2025: 2
- 2026: 16
-
Local Information Disclosure Vulnerability in io.netty:netty-codec-http this entry
Know which vulnerabilities affect your application
With the DockRay integration and software inventory enabled, DockRay checks reported component versions against known vulnerabilities and notifies you about confirmed matches. Coverage depends on the supported technology and available advisory data.