CVE-2026-28367

Published Mar 27, 2026

Last updated 6 days ago

CVSS high 8.7

Overview

Description
A flaw was found in Undertow. A remote attacker can exploit this vulnerability by sending `\r\r\r` as a header block terminator. This can be used for request smuggling with certain proxy servers, such as older versions of Apache Traffic Server and Google Cloud Classic Application Load Balancer, potentially leading to unauthorized access or manipulation of web requests.
Source
secalert@redhat.com
NVD status
Analyzed
Products
build_of_apache_camel_-_hawtio, build_of_apache_camel_for_spring_boot, data_grid, fuse, jboss_enterprise_application_platform, jboss_enterprise_application_platform_expansion_pack, process_automation, single_sign-on, undertow

Risk scores

CVSS 3.1

Type
Primary
Base score
9.1
Impact score
5.2
Exploitability score
3.9
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Severity
CRITICAL

Weaknesses

secalert@redhat.com
CWE-444

Social media

Hype score
Not currently trending

Configurations

Related CVEs

  1. 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.•CVE-2026-28369
  2. 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.•CVE-2026-28368
  3. A flaw was found in Keycloak. An administrator with `manage-clients` permission can exploit a misconfiguration where this permission is equivalent to `manage-permissions`. This allows the administrator to escalate privileges and gain control over roles, users, or other administrative functions within the realm. This privilege escalation can occur when admin permissions are enabled at the realm level.•CVE-2026-3121
  4. A flaw was found in Keycloak. An authenticated attacker can perform Server-Side Request Forgery (SSRF) by manipulating the `client_session_host` parameter during refresh token requests. This occurs when a Keycloak client is configured to use the `backchannel.logout.url` with the `application.session.host` placeholder. Successful exploitation allows the attacker to make HTTP requests from the Keycloak server’s network context, potentially probing internal networks or internal APIs, leading to information disclosure.•CVE-2026-4874
  5. A flaw was found in Undertow. A remote attacker could exploit this vulnerability by sending an HTTP GET request containing multipart/form-data content. If the underlying application processes parameters using methods like `getParameterMap()`, the server prematurely parses and stores this content to disk. This could lead to resource exhaustion, potentially resulting in a Denial of Service (DoS).•CVE-2026-3260

References

Sources include official advisories and independent security research.