Red Hat Undertow prior 2.2.30.SP1/2.3.10.SP3 HTTP Upgrade WriteTimeoutStreamSinkConduit resource consumption

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6.3	$0-$5k	0.00

Summaryinfo

A vulnerability was found in Red Hat Undertow. It has been classified as problematic. This affects the function WriteTimeoutStreamSinkConduit of the component HTTP Upgrade Handler. This manipulation causes resource consumption. The identification of this vulnerability is CVE-2024-1635. It is possible to initiate the attack remotely. There is no exploit available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability has been found in Red Hat Undertow and classified as problematic. Affected by this vulnerability is the function WriteTimeoutStreamSinkConduit of the component HTTP Upgrade Handler. The manipulation with an unknown input leads to a resource consumption vulnerability. The CWE definition for the vulnerability is CWE-400. The product does not properly control the allocation and maintenance of a limited resource, thereby enabling an actor to influence the amount of resources consumed, eventually leading to the exhaustion of available resources. As an impact it is known to affect availability. The summary by CVE is:

A vulnerability was found in Undertow. This vulnerability impacts a server that supports the wildfly-http-client protocol. Whenever a malicious user opens and closes a connection with the HTTP port of the server and then closes the connection immediately, the server will end with both memory and open file limits exhausted at some point, depending on the amount of memory available. At HTTP upgrade to remoting, the WriteTimeoutStreamSinkConduit leaks connections if RemotingConnection is closed by Remoting ServerConnectionOpenListener. Because the remoting connection originates in Undertow as part of the HTTP upgrade, there is an external layer to the remoting connection. This connection is unaware of the outermost layer when closing the connection during the connection opening procedure. Hence, the Undertow WriteTimeoutStreamSinkConduit is not notified of the closed connection in this scenario. Because WriteTimeoutStreamSinkConduit creates a timeout task, the whole dependency tree leaks via that task, which is added to XNIO WorkerThread. So, the workerThread points to the Undertow conduit, which contains the connections and causes the leak.

The weakness was shared 02/20/2024. It is possible to read the advisory at access.redhat.com. This vulnerability is known as CVE-2024-1635 since 02/19/2024. Technical details of the vulnerability are known, but there is no available exploit. The attack technique deployed by this issue is T1499 according to MITRE ATT&CK.

The vulnerability scanner Nessus provides a plugin with the ID 240509 (RHEL 7 : Red Hat JBoss Enterprise Application Platform 7.3.14 Security update (Important) (RHSA-2025:9583)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 2.2.30.SP1 or 2.3.10.SP3 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (240509). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Vendor

• Red Hat

Name

• Undertow

License

• free

Website

• Vendor: https://www.redhat.com/

CPE 2.3info

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CPE 2.2info

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CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.4
VulDB Meta Temp Score: 6.3

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

CNA Base Score: 7.5
CNA Vector (Red Hat, Inc.): 🔍

CVSSv2info

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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Resource consumption
CWE: CWE-400 / CWE-404
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 240509
Nessus Name: RHEL 7 : Red Hat JBoss Enterprise Application Platform 7.3.14 Security update (Important) (RHSA-2025:9583)

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Undertow 2.2.30.SP1/2.3.10.SP3

Timelineinfo

02/19/2024 🔍
02/20/2024 +1 days 🔍
02/20/2024 +0 days 🔍
06/26/2025 +492 days 🔍

Sourcesinfo

Vendor: redhat.com

Advisory: access.redhat.com
Status: Confirmed

CVE: CVE-2024-1635 (🔍)
GCVE (CVE): GCVE-0-2024-1635
GCVE (VulDB): GCVE-100-254119

Entryinfo

Created: 02/20/2024 07:18
Updated: 06/26/2025 06:07
Changes: 02/20/2024 07:18 (49), 02/21/2024 09:17 (2), 09/17/2024 00:59 (16), 06/26/2025 06:07 (2)
Complete: 🔍
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

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