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TI-2026-22646 Aliases CVE-2026-28369GHSA-vqqj-9cmv-hx43

Undertow: undertow: request smuggling via malformed http request headers

Priority MEDIUM 42CWE-444Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
High · High · None
Fix status
Partial Red Hat: 3 fixed, 9 without a fix

Attack profile from CVSS 3.1 · NVD. Fix status from CNA, GitHub and Red Hat.

Summary

A flaw was found in Undertow. When Undertow receives an HTTP request where the first header line starts with one or more spaces, it incorrectly processes the request by stripping these leading spaces. This behavior, which violates HTTP standards, can be exploited by a remote attacker to perform request smuggling. Request smuggling allows an attacker to bypass security mechanisms, access restricted information, or manipulate web caches, potentially leading to unauthorized actions or data exposure.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00689 52nd percentileScored 2026-11-07
Fix Partial io.undertow:undertow-core (Maven): 2.2.40.Final, 2.3.25.FinalRed Hat: 2 advisoriesRed Hat: 3 fixed, 9 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
Red HatRed Hat JBoss Enterprise Application Platform 8.1.6—2.3.24.SP2-redhat-00001Patch availableCNA
Red HatRed Hat JBoss Enterprise Application Platform 8.1 for RHEL 8—2.40.0-7.redhat_00015.1.el8eapPatch availableCNA
Red HatRed Hat JBoss Enterprise Application Platform 8.1 for RHEL 8—801.6.1-1.GA_redhat_00001.1.el8eapPatch availableCNA
Red HatRed Hat JBoss Enterprise Application Platform 8.1 for RHEL 8—2.3.24-3.SP2_redhat_00001.1.el8eapPatch availableCNA
Red HatRed Hat JBoss Enterprise Application Platform 8.1 for RHEL 8—8.1.6-7.GA_redhat_00010.1.el8eapPatch availableCNA
Red HatRed Hat JBoss Enterprise Application Platform 8.1 for RHEL 9—2.40.0-7.redhat_00015.1.el9eapPatch availableCNA
Red HatRed Hat JBoss Enterprise Application Platform 8.1 for RHEL 9—801.6.1-1.GA_redhat_00001.1.el9eapPatch availableCNA
Red HatRed Hat JBoss Enterprise Application Platform 8.1 for RHEL 9—2.3.24-3.SP2_redhat_00001.1.el9eapPatch availableCNA
Red HatRed Hat JBoss Enterprise Application Platform 8.1 for RHEL 9—8.1.6-7.GA_redhat_00010.1.el9eapPatch availableCNA
Red HatRed Hat build of Apache Camel for Spring Boot 4——No fix listedCNA
Red HatRed Hat build of Apache Camel - HawtIO 4——Not affectedCNA
Red HatRed Hat Data Grid 8——No fix listedCNA
Red HatRed Hat Enterprise Linux 10——Not affectedCNA
Red HatRed Hat Enterprise Linux 8——Not affectedCNA
Red HatRed Hat Enterprise Linux 8——Not affectedCNA
Red HatRed Hat Enterprise Linux 9——No fix listedCNA
Red HatRed Hat Fuse 7——No fix listedCNA
Red HatRed Hat JBoss Enterprise Application Platform 7——No fix listedCNA
Red HatRed Hat JBoss Enterprise Application Platform 8——No fix listedCNA
Red HatRed Hat JBoss Enterprise Application Platform 8——No fix listedCNA
Red HatRed Hat JBoss Enterprise Application Platform Expansion Pack——No fix listedCNA
Red HatRed Hat JBoss Enterprise Application Platform Expansion Pack——No fix listedCNA
Red HatRed Hat JBoss Enterprise Application Platform Expansion Pack——Not affectedCNA
Red HatRed Hat Process Automation 7——No fix listedCNA
Red HatRed Hat Single Sign-On 7——No fix listedCNA
—io.undertow:undertow-core (Maven)before 2.2.40.Final2.2.40.FinalPatch availableGHSA-vqqj-9cmv-hx43
—io.undertow:undertow-core (Maven)2.3.0.Final to before 2.3.25.Final2.3.25.FinalPatch availableGHSA-vqqj-9cmv-hx43
  • Red Hat JBoss Enterprise Application Platform 8.1.6 VendorRed Hat Affected — Fixed in 2.3.24.SP2-redhat-00001 Patch available CNA
  • Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 8 VendorRed Hat Affected — Fixed in 2.40.0-7.redhat_00015.1.el8eap Patch available CNA
  • Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 8 VendorRed Hat Affected — Fixed in 801.6.1-1.GA_redhat_00001.1.el8eap Patch available CNA
  • Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 8 VendorRed Hat Affected — Fixed in 2.3.24-3.SP2_redhat_00001.1.el8eap Patch available CNA
  • Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 8 VendorRed Hat Affected — Fixed in 8.1.6-7.GA_redhat_00010.1.el8eap Patch available CNA
  • Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 9 VendorRed Hat Affected — Fixed in 2.40.0-7.redhat_00015.1.el9eap Patch available CNA
  • Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 9 VendorRed Hat Affected — Fixed in 801.6.1-1.GA_redhat_00001.1.el9eap Patch available CNA
  • Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 9 VendorRed Hat Affected — Fixed in 2.3.24-3.SP2_redhat_00001.1.el9eap Patch available CNA
  • Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 9 VendorRed Hat Affected — Fixed in 8.1.6-7.GA_redhat_00010.1.el9eap Patch available CNA
  • Red Hat build of Apache Camel for Spring Boot 4 VendorRed Hat Affected — Fixed in — No fix listed CNA
  • Red Hat build of Apache Camel - HawtIO 4 VendorRed Hat Affected — Fixed in — Not affected CNA
  • Red Hat Data Grid 8 VendorRed Hat Affected — Fixed in — No fix listed CNA
  • Red Hat Enterprise Linux 10 VendorRed Hat Affected — Fixed in — Not affected CNA
  • Red Hat Enterprise Linux 8 VendorRed Hat Affected — Fixed in — Not affected CNA
  • Red Hat Enterprise Linux 8 VendorRed Hat Affected — Fixed in — Not affected CNA
  • Red Hat Enterprise Linux 9 VendorRed Hat Affected — Fixed in — No fix listed CNA
  • Red Hat Fuse 7 VendorRed Hat Affected — Fixed in — No fix listed CNA
  • Red Hat JBoss Enterprise Application Platform 7 VendorRed Hat Affected — Fixed in — No fix listed CNA
  • Red Hat JBoss Enterprise Application Platform 8 VendorRed Hat Affected — Fixed in — No fix listed CNA
  • Red Hat JBoss Enterprise Application Platform 8 VendorRed Hat Affected — Fixed in — No fix listed CNA
  • Red Hat JBoss Enterprise Application Platform Expansion Pack VendorRed Hat Affected — Fixed in — No fix listed CNA
  • Red Hat JBoss Enterprise Application Platform Expansion Pack VendorRed Hat Affected — Fixed in — No fix listed CNA
  • Red Hat JBoss Enterprise Application Platform Expansion Pack VendorRed Hat Affected — Fixed in — Not affected CNA
  • Red Hat Process Automation 7 VendorRed Hat Affected — Fixed in — No fix listed CNA
  • Red Hat Single Sign-On 7 VendorRed Hat Affected — Fixed in — No fix listed CNA
  • io.undertow:undertow-core (Maven) Vendor— Affected before 2.2.40.Final Fixed in 2.2.40.Final Patch available GHSA-vqqj-9cmv-hx43
  • io.undertow:undertow-core (Maven) Vendor— Affected 2.3.0.Final to before 2.3.25.Final Fixed in 2.3.25.Final Patch available GHSA-vqqj-9cmv-hx43

CPE configurations NVD · 11

CPEVersionsRoleVendor
cpe:2.3:a:redhat:build_of_apache_camel_-_hawtio:4.0:*:*:*:*:*:*:*4.0VulnerableRed Hat
cpe:2.3:a:redhat:build_of_apache_camel_for_spring_boot:4.0:*:*:*:*:*:*:*4.0VulnerableRed Hat
cpe:2.3:a:redhat:data_grid:8.0:*:*:*:*:*:*:*8.0VulnerableRed Hat
cpe:2.3:a:redhat:fuse:7.0.0:*:*:*:*:*:*:*7.0.0VulnerableRed Hat
cpe:2.3:a:redhat:jboss_enterprise_application_platform:7.0.0:*:*:*:*:*:*:*7.0.0VulnerableRed Hat
cpe:2.3:a:redhat:jboss_enterprise_application_platform:8.0.0:*:*:*:*:*:*:*8.0.0VulnerableRed Hat
cpe:2.3:a:redhat:jboss_enterprise_application_platform_expansion_pack:-:*:*:*:*:*:*:*not specified by NVDVulnerableRed Hat
cpe:2.3:a:redhat:process_automation:7.0:*:*:*:*:*:*:*7.0VulnerableRed Hat
cpe:2.3:a:redhat:single_sign-on:7.0:*:*:*:*:*:*:*7.0VulnerableRed Hat
cpe:2.3:a:redhat:undertow:-:*:*:*:*:*:*:*not specified by NVDVulnerableRed Hat
  • cpe:2.3:a:redhat:build_of_apache_camel_-_hawtio:4.0:*:*:*:*:*:*:* Versions 4.0 Vulnerable ·Red Hat
  • cpe:2.3:a:redhat:build_of_apache_camel_for_spring_boot:4.0:*:*:*:*:*:*:* Versions 4.0 Vulnerable ·Red Hat
  • cpe:2.3:a:redhat:data_grid:8.0:*:*:*:*:*:*:* Versions 8.0 Vulnerable ·Red Hat
  • cpe:2.3:a:redhat:fuse:7.0.0:*:*:*:*:*:*:* Versions 7.0.0 Vulnerable ·Red Hat
  • cpe:2.3:a:redhat:jboss_enterprise_application_platform:7.0.0:*:*:*:*:*:*:* Versions 7.0.0 Vulnerable ·Red Hat
  • cpe:2.3:a:redhat:jboss_enterprise_application_platform:8.0.0:*:*:*:*:*:*:* Versions 8.0.0 Vulnerable ·Red Hat
  • cpe:2.3:a:redhat:jboss_enterprise_application_platform_expansion_pack:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·Red Hat
  • cpe:2.3:a:redhat:process_automation:7.0:*:*:*:*:*:*:* Versions 7.0 Vulnerable ·Red Hat
  • cpe:2.3:a:redhat:single_sign-on:7.0:*:*:*:*:*:*:* Versions 7.0 Vulnerable ·Red Hat
  • cpe:2.3:a:redhat:undertow:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·Red Hat
Show 1 more CPE
CPEVersionsRoleVendor
cpe:2.3:o:redhat:enterprise_linux:9.0:*:*:*:*:*:*:*9.0VulnerableRed Hat
  • cpe:2.3:o:redhat:enterprise_linux:9.0:*:*:*:*:*:*:* Versions 9.0 Vulnerable ·Red Hat

Remediation

  • Fix · GHSA-vqqj-9cmv-hx43 io.undertow:undertow-core (Maven) Fixed in 2.2.40.Final Advisory →
  • Fix · GHSA-vqqj-9cmv-hx43 io.undertow:undertow-core (Maven) Fixed in 2.3.25.Final Advisory →

Red Hat 2 advisories

  • RHSA-2026:25125 Released 2026-06-10 · Red Hat rating Important
    Red Hat JBoss Enterprise Application Platform 8.1.6 security update
    • Red Hat JBoss EAP 8.1 for RHEL 8 eap8-activemq-artemis-2.40.0-7.redhat_00015.1.el8eap, eap8-activemq-artemis-cli-2.40.0-7.redhat_00015.1.el8eap, eap8-activemq-artemis-commons-2.40.0-7.redhat_00015.1.el8eap +19
    • Red Hat JBoss EAP 8.1 for RHEL 9 eap8-activemq-artemis-2.40.0-7.redhat_00015.1.el9eap, eap8-activemq-artemis-cli-2.40.0-7.redhat_00015.1.el9eap, eap8-activemq-artemis-commons-2.40.0-7.redhat_00015.1.el9eap +19
  • RHSA-2026:25126 Released 2026-06-10 · Red Hat rating Important
    Red Hat JBoss Enterprise Application Platform 8.1.6 security update
    • Red Hat JBoss Enterprise Application Platform 8.1.6 io.undertow.undertow-core-2.3.24.SP2-redhat-00001.jar, org.jboss.activemq.artemis.integration.artemis-wildfly-integration-2.0.3.Final-redhat-00001.jar

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Advisory ·

    Red Hat Data Grid 8, Red Hat Enterprise Linux 10 and 13 more products — RHSA-2026:25125

    3 records Highest priority Priority MEDIUM 3 MEDIUM

    Other records, highest priority first

    • TI-2026-22645 Undertow: undertow: request smuggling via inconsistent header parsingPriority MEDIUM 43
    • TI-2026-22644 Undertow: undertow: request smuggling via `\r\r\r` as a header block terminatorPriority MEDIUM 42
    Show all 3 records → Advisory →
  • Advisory ·

    Red Hat Data Grid 8, Red Hat Enterprise Linux 10 and 13 more products — RHSA-2026:25126

    3 records Highest priority Priority MEDIUM 3 MEDIUM

    Other records, highest priority first

    • TI-2026-22645 Undertow: undertow: request smuggling via inconsistent header parsingPriority MEDIUM 43
    • TI-2026-22644 Undertow: undertow: request smuggling via `\r\r\r` as a header block terminatorPriority MEDIUM 42
    Show all 3 records → Advisory →

Vendor assessments

Red Hat

Red Hat rating: Important. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Data Grid 8AffectedNo fix planned: Will not fix
Red Hat Enterprise Linux 9AffectedNo fix yet
Red Hat Fuse 7AffectedNo fix planned: Will not fix
Red Hat JBoss Enterprise Application Platform 7AffectedNo fix planned: Will not fix
Red Hat JBoss Enterprise Application Platform 8AffectedNo fix yet
Red Hat JBoss Enterprise Application Platform Expansion PackAffectedNo fix yet
Red Hat Process Automation 7AffectedNo fix planned: Will not fix
Red Hat Single Sign-On 7AffectedNo fix yet: Fix deferred
Red Hat build of Apache Camel for Spring Boot 4AffectedNo fix yet: Fix deferred
Red Hat JBoss EAP 8.1 for RHEL 8Fixed RHSA-2026:25125
Red Hat JBoss EAP 8.1 for RHEL 9Fixed RHSA-2026:25125
Red Hat JBoss Enterprise Application Platform 8.1.6Fixed RHSA-2026:25126
Not affected: 5 products
  • Red Hat Enterprise Linux 10
  • Red Hat Enterprise Linux 8
  • Red Hat JBoss Enterprise Application Platform 8.1.6
  • Red Hat JBoss Enterprise Application Platform Expansion Pack
  • Red Hat build of Apache Camel - HawtIO 4

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-28369
  2. 2026-10-03 Alias added: GHSA-vqqj-9cmv-hx43
  3. 2026-10-15 Fix available: io.undertow/[email protected] · CNA
  4. 2026-10-16 Fix available: Red Hat JBoss Enterprise Application Platform 8.1.6 · Red Hat
  5. 2026-11-04 Fix available: Maven/io.undertow:[email protected], Maven/io.undertow:[email protected] · GHSA-vqqj-9cmv-hx43
  6. 2026-11-04 3 new references · GHSA-vqqj-9cmv-hx43

References

Advisory 5

Other 4

  • TI-2026-22645 Undertow: undertow: request smuggling via inconsistent header parsing CVSS 3.1CRITICAL 9.1
  • TI-2026-22644 Undertow: undertow: request smuggling via `\r\r\r` as a header block terminator CVSS 3.1CRITICAL 9.1
  • TI-2024-07308 Undertow: improper state management in proxy protocol parsing causes information leakage CVSS 3.1HIGH 7.5

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences