CVE-2026-28368
undertow: Undertow: Request smuggling via inconsistent header parsing
Severity by source
Trivy's own label is CRITICAL. Rated critical by NVD. Rated lower by GHSA (high), Red Hat (high).
Description
A flaw was found in Undertow. This vulnerability allows a remote attacker to construct specially crafted requests where header names are parsed differently by Undertow compared to upstream proxies. This discrepancy in header interpretation can be exploited to launch request smuggling attacks, potentially bypassing security controls and accessing unauthorized resources.
Affected packages and fixed versions
| Source | Package | Fixed in |
|---|---|---|
| debian 14 | undertow | no fix listed |
| maven::GitHub Security Advisory Maven | io.undertow:undertow-parent | no fix listed |
| rapidfort alma 9 | pki-resteasy-client, pki-resteasy-core, pki-resteasy-jackson2-provider and 1 more | no fix listed |
| rapidfort Oracle Linux 9 | pki-resteasy-client, pki-resteasy-core, pki-resteasy-jackson2-provider and 1 more | no fix listed |
| rapidfort rocky 9 | resteasy | no fix listed |
| Red Hat | pki-resteasy-client, pki-resteasy-core, pki-resteasy-jackson2-provider and 3 more | no fix listed |
Show all 17 entries from 6 sources
| Source | Package | Fixed in |
|---|---|---|
| debian 14 | undertow | no fix listed |
| maven::GitHub Security Advisory Maven | io.undertow:undertow-parent | no fix listed |
| rapidfort alma 9 | pki-resteasy-client | no fix listed |
| rapidfort alma 9 | pki-resteasy-core | no fix listed |
| rapidfort alma 9 | pki-resteasy-jackson2-provider | no fix listed |
| rapidfort alma 9 | pki-resteasy-servlet-initializer | no fix listed |
| rapidfort Oracle Linux 9 | pki-resteasy-client | no fix listed |
| rapidfort Oracle Linux 9 | pki-resteasy-core | no fix listed |
| rapidfort Oracle Linux 9 | pki-resteasy-jackson2-provider | no fix listed |
| rapidfort Oracle Linux 9 | pki-resteasy-servlet-initializer | no fix listed |
| rapidfort rocky 9 | resteasy | no fix listed |
| Red Hat | pki-resteasy-client | no fix listed |
| Red Hat | pki-resteasy-core | no fix listed |
| Red Hat | pki-resteasy-jackson2-provider | no fix listed |
| Red Hat | pki-resteasy-servlet-initializer | no fix listed |
| Red Hat | resteasy | no fix listed |
| Red Hat | undertow-core | no fix listed |
References
- https://access.redhat.com/errata/RHSA-2026:25125
- https://access.redhat.com/errata/RHSA-2026:25126
- https://access.redhat.com/security/cve/CVE-2026-28368
- https://bugzilla.redhat.com/show_bug.cgi?id=2443261
- https://github.com/undertow-io/undertow
- https://nvd.nist.gov/vuln/detail/CVE-2026-28368
- https://www.cve.org/CVERecord?id=CVE-2026-28368