CVE-2024-3884
High
Description
A flaw was found in Undertow that can cause remote denial of service attacks. When the server uses the FormEncodedDataDefinition.doParse(StreamSourceChannel) method to parse large form data encoding with application/x-www-form-urlencoded, the method will cause an OutOfMemory issue. This flaw allows unauthorized users to cause a remote denial of service (DoS) attack.
SeverityHigh
CVSS7.5
Exploit probability—
ProductIo.undertow:undertow-core
PublishedDec 3, 2025
First seenDec 3, 2025
Weakness typeCWE-20Improper input validation
How to fix
Update
- io.undertow:undertow-core2.2.39.Final, 2.4.0.Beta1, 2.3.21.Final or later
Vendor advisories
- access.redhat.com/errata/RHSA-2026:0383
- access.redhat.com/errata/RHSA-2026:0384
- access.redhat.com/errata/RHSA-2026:0386
- access.redhat.com/errata/RHSA-2026:3889
- access.redhat.com/errata/RHSA-2026:3891
- access.redhat.com/errata/RHSA-2026:3892
- access.redhat.com/errata/RHSA-2026:4915
- access.redhat.com/errata/RHSA-2026:4916
- access.redhat.com/errata/RHSA-2026:4917
- access.redhat.com/errata/RHSA-2026:4924
- access.redhat.com/errata/RHSA-2026:6011
- access.redhat.com/errata/RHSA-2026:6012
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| io.undertow:undertow-coreMaven | v < 2.2.39.Final, 2.4.0.Alpha1 ≤ v < 2.4.0.Beta1, 2.3.0.Alpha1 ≤ v < 2.3.21.Final | 2.2.39.Final, 2.4.0.Beta1, 2.3.21.Final |
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