Attack ChainAIDerived
Hypothetical attack flow derived from CVE metadata – not a confirmed exploit chain
-
ReconAuthenticate with low-privileged application account
-
DeliveryIdentify user-controlled Qute template input surface
-
ExploitInject crafted Enum-based template expression
-
InstallTrigger template rendering via normal application request
-
C2ReflectionValueResolver resolves Enum member bypassing access controls
-
ExecuteInvoke privileged Java reflection methods
-
ImpactExecute arbitrary OS commands as application service account
Vulnerability Assessment
| Weakness |
CWE
ASVS 5.0
V1 - Encoding and Sanitization Template injection prevention
|
| Exploitation Conditions | Exploitation requires that the attacker hold a low-privileged authenticated session (PR:L per CVSS) in a Quarkus application that exposes user-controllable Qute template text - this is the critical non-default precondition. Applications that render Qute templates entirely from static, developer-controlled template files are not exposed; the vulnerability only materializes when user input reaches the Qute rendering pipeline as template expressions (not just data values). The flaw is specifically triggered through Enum-type expression resolution in ReflectionValueResolver, meaning templates must be able to reference Enum members in a way the resolver processes. The CVSS S:U (Unchanged scope) indicates exploitation is bounded to the vulnerable application's own process context. Limiting factors: requires authenticated access; requires application functionality that accepts user-supplied template syntax; network exploitation only reaches systems where such features are accessible; no user interaction from a victim is needed once the attacker controls the template. |
| Impact | The CVSS 8.8 score (AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H) accurately reflects the risk profile: network-reachable exploitation with low attack complexity and only low-privilege authentication required, yielding full confidentiality, integrity, and availability impact. The PR:L metric is the key limiting factor - exploitation is not open to anonymous Internet users but requires an account or session capable of submitting or influencing Qute template text, which is an application-specific capability. No public exploit or CISA KEV listing has been identified, and the EPSS signal is absent from the provided data, meaning the current exploitation baseline appears low. However, SSTI vulnerabilities in templating engines are well-understood and template injection payloads targeting Java reflection are routinely weaponized; once application surface is identified, exploitation complexity is low. Even a mid-sized enterprise IT team in leszno running Quarkus-based web portals with user-editable content should treat this as urgent if any application tier accepts user-supplied template fragments. The absence of a KEV entry should not be interpreted as safety: the gap between SSTI disclosure and available exploit tooling is typically short once a proof-of-concept technique is documented. Priority is elevated for multi-tenant SaaS platforms, email automation systems, and internal portals where low-privileged users interact with templating features. |
| Exploit ScenarioDerived | An authenticated user with access to a Quarkus application's template editor - such as a content author in a CMS, a marketing user configuring email templates, or an internal report builder - submits a crafted template expression that references an Enum type in a way that bypasses ReflectionValueResolver's access controls, exposing Java reflection internals. The attacker chains reflected method calls to invoke Runtime.exec() or equivalent, achieving arbitrary OS command execution under the application server's service account. No public POC has been identified at time of analysis, but the technique class is well-documented in SSTI research. |
Get an e-mail when this CVE is exploited, patched or re-scored. Free account.
Alert meAnalysisAIv1 – Aug 31, 2026
Server-side template injection in the Qute template engine's ReflectionValueResolver allows authenticated remote attackers with the ability to influence template content to bypass Java sandbox restrictions and execute arbitrary OS commands on the server. Affected Red Hat products include Red Hat Build of Quarkus, Red Hat Build of Apache Camel 4 for Quarkus 3, and the JBoss EAP Expansion Pack. No public exploit code or CISA KEV entry has been identified at time of analysis, but the CVSS score of 8.8 and full C/I/A impact make this a high-priority patching target for any Quarkus deployment exposing user-influenced template rendering.
RemediationAI
Apply the Red Hat security update referenced at https://access.redhat.com/security/cve/CVE-2026-12894 as the primary remediation action; no exact patched version number was confirmed in the input data, so consult the advisory directly for the specific errata package version. As a compensating control where patching is not immediately possible, audit all application surfaces that allow users to supply or modify Qute template text and restrict or eliminate that capability - disabling user-controlled template input entirely removes the attack surface without requiring a code change, though it may break business functionality such as custom email templates or report builders. If user-controlled templates are a required business feature, consider sandboxing the Qute rendering process in a restricted JVM with a security manager policy that blocks reflective access to java.lang internals, though Java security manager is deprecated in newer JDKs and its reliability as a control is limited. Monitor the Red Hat Bugzilla entry (https://bugzilla.redhat.com/show_bug.cgi?id=2491319) for patch release notifications.
Affects your stack
Find out whether the stacks and servers you run are on an affected version.
Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
Qute is Quarkus's reactive, type-safe template engine used to generate dynamic HTML, email, and other text content. CWE-1336 (Improper Neutralization of Special Elements Used in a Template Engine) describes the root cause class: SSTI vulnerabilities arise when user-controlled input reaches the template rendering layer without adequate sanitization or sandboxing. The specific flaw resides in ReflectionValueResolver, which uses Java reflection to dynamically look up property and method values on data objects. When resolving members of Java Enum types, this resolver fails to enforce the expected access restrictions, inadvertently exposing privileged Java internal methods. An attacker who can inject or control Qute template expressions - for example, through a CMS, email template editor, or report generator - can craft Enum-based expressions that traverse the reflection API to invoke arbitrary Java methods, ultimately achieving remote code execution. CPE data identifies affected products as cpe:2.3:a:red_hat:red_hat_build_of_quarkus and cpe:2.3:a:red_hat:red_hat_build_of_apache_camel_4_for_quarkus_3 (all versions per wildcard CPE) and cpe:2.3:a:red_hat:red_hat_jboss_enterprise_application_platform_expansion_pack.
Know when Java gets its next vulnerability
- Watch products and get an email when something new is published
- Check this CVE against your own stack and servers
- Exploit and PoC references, threat intelligence from 22 sources
No credit card · 7-day full trial
Severity by source
AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Network vector and low complexity are correct; PR:L reflects that influencing template text requires an authenticated application session, not anonymous access.
Primary rating from Vendor (redhat).
CVSS VectorVendor: redhat
DescriptionCVE.org
A flaw was found in the Qute template engine, which is used by Quarkus to generate dynamic content like HTML pages or emails. The issue exists in the component responsible for looking up data values (ReflectionValueResolver), which fails to properly block access to sensitive Java internal functions when processing certain data types like Enums. An attacker who can provide or influence the template text can exploit this bypass to take control of the server by executing unauthorized commands.
Executive ViewAI
Red Hat Quarkus and JBoss EAP users face a high-severity template injection vulnerability in the Qute engine allowing attackers to execute arbitrary operating system commands and achieve complete system compromise. Organizations running these Red Hat products must immediately assess exposure and implement controls, as no vendor patch is currently available.
No vendor-released patch identified at time of analysis. Interim mitigations include: (1) strict input validation preventing untrusted data from being processed as template content, (2) runtime least-privilege permissions limiting exploitation blast radius, (3) network segmentation restricting access to vulnerable applications, (4) disable or restrict use of Qute ReflectionValueResolver where functional requirements permit, (5) comprehensive logging and alerting on process execution attempts, and (6) periodic testing of compensating control effectiveness.
Threat Intelligence Overview
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Information disclosure occurs when an application unintentionally exposes sensitive data that aids attackers in reconnaissance or directly compromises security.
Affected Products (CPE)CVE.org
Oracle Java SE 7 Update 6 and earlier contains multiple sandbox bypass vulnerabilities via the ClassFinder and forName m
Remote code execution in IBM Sterling B2B Integrator, Sterling Integrator, and Tivoli Common Reporting allows unauthenti
Java Runtime Environment sandbox bypass via incorrect image channel verification in 2D component allows remote unauthent
Oracle Java SE JDK/JRE 7 and 6 Update 27 and earlier allows remote code execution with complete system compromise throug
JBoss Seam 2 in Red Hat JBoss EAP 4.3.0 fails to sanitize JBoss Expression Language inputs, allowing remote attackers to
Unspecified vulnerability in the Java Runtime Environment (JRE) component in Oracle Java SE 7 update 4 and earlier, 6 up
Multiple vulnerabilities in Oracle Java 7 before Update 11 allow remote attackers to execute arbitrary code by (1) using
Unspecified vulnerability in the Java Runtime Environment (JRE) component in Oracle Java SE 7 Update 2 and earlier, 6 Up
The WLS Security component in Oracle WebLogic Server 10.3.6.0, 12.1.2.0, 12.1.3.0, and 12.2.1.0 allows remote attackers
Unspecified vulnerability in the Java Runtime Environment (JRE) component in Oracle Java SE 7 Update 7 and earlier allow
Remote unauthenticated attackers can execute arbitrary code on Adobe ColdFusion servers through Java deserialization fla
The ExceptionDelegator component in Apache Struts before 2.2.3.1 interprets parameter values as OGNL expressions during
EUVD-2026-68505
GHSA-w5gv-wrvc-9hx8
NVD
CVE.org
EPSS
Vulnrichment
Exploit-DB