CVE-2026-21754: HCL Hive Information Disclosure Vulnerability

CVE-2026-21754 Overview

CVE-2026-21754 affects HCL Hive with multiple infrastructure and network configuration weaknesses. The flaws could enable unauthorized lateral movement, container breakout, and exposure of sensitive data transmitted over internal communication channels. The weakness is categorized under [CWE-1004], which covers sensitive cookies without the HttpOnly flag and related insecure transport controls.

An attacker exploiting this issue operates over the network and requires user interaction to succeed. Successful exploitation impacts confidentiality and integrity of internal traffic and workload boundaries within Hive deployments.

Critical Impact
Improper network configuration in HCL Hive can allow attackers to move laterally between containers, escape workload isolation, and read sensitive internal traffic.

Affected Products

HCL Hive (versions specified in the vendor advisory)
Container workloads deployed alongside HCL Hive services
Internal service-to-service communication channels used by Hive

Discovery Timeline

2026-08-25 - CVE-2026-21754 published to NVD
2026-08-25 - Last updated in NVD database

Technical Details for CVE-2026-21754

Vulnerability Analysis

CVE-2026-21754 groups multiple configuration weaknesses in HCL Hive rather than a single memory-safety bug. The issues span network segmentation, container isolation, and protection of internal traffic. Attackers who reach the network path can pivot between components that should remain isolated.

The advisory maps the weakness family to [CWE-1004]. In Hive, this manifests through insufficient transport hardening and missing security attributes on session and communication artifacts. When combined with permissive container and network configurations, an adversary can observe or influence data flowing between internal services.

Exploitation requires user interaction, which typically means an authenticated user must trigger an action that exposes internal state. The scope remains unchanged, but the attacker gains partial confidentiality and integrity impact against workloads that assumed the internal network was trusted.

Root Cause

The root cause is insecure default network and container configuration. Internal traffic lacks strict transport controls, cookies and tokens are exposed to client-side contexts, and container boundaries do not enforce strong isolation. These defaults let an attacker leverage a foothold in one component to reach adjacent components.

Attack Vector

An attacker on the network coerces or waits for a legitimate user to interact with a crafted request. The interaction leaks session material or exposes internal service endpoints. The attacker then uses the leaked context to reach other Hive components, escape a container namespace, or capture cleartext internal traffic. Refer to the HCL Software Knowledge Base Article for vendor-specific technical detail.

No public exploit code, proof of concept, or CISA KEV entry exists for this CVE at publication.

Detection Methods for CVE-2026-21754

Indicators of Compromise

Unexpected east-west traffic between HCL Hive containers that normally do not communicate
Session cookies or tokens appearing in browser storage or client-side scripts when they should be server-only
Container processes reading files or sockets outside their declared namespace
Cleartext protocol usage on internal service ports that should enforce TLS

Detection Strategies

Baseline expected service-to-service traffic in the Hive cluster and alert on deviations
Inspect HTTP responses for missing HttpOnly, Secure, and SameSite attributes on session cookies
Monitor container runtime telemetry for namespace escapes, unexpected mount calls, and privileged operations
Correlate authentication events with sudden access to internal-only endpoints from user sessions

Monitoring Recommendations

Enable flow logs for the network segments hosting HCL Hive and retain them for retrospective analysis
Instrument container runtimes with syscall auditing focused on clone, unshare, and setns
Log all internal API calls with source identity, destination service, and TLS status
Alert on any plaintext credential material observed on internal channels

How to Mitigate CVE-2026-21754

Immediate Actions Required

Apply the vendor guidance in the HCL Software Knowledge Base Article as soon as it is available for your Hive version
Restrict network reachability between Hive components to only the flows required for operation
Rotate session secrets, API tokens, and internal service credentials after remediation
Review container images and runtime settings to remove privileged capabilities that are not required

Patch Information

HCL Software has published remediation guidance in KB0133342. Apply the fixes and configuration changes recommended by HCL for your deployed version of Hive. Confirm the patched configuration in a staging environment before rolling to production.

Workarounds

Enforce TLS on all internal service communication, including sidecar and management ports
Set HttpOnly, Secure, and SameSite=Strict on session cookies where the application allows
Apply Kubernetes NetworkPolicy or equivalent segmentation to block lateral traffic by default
Run containers with a read-only root filesystem and drop Linux capabilities not required by the workload

bash

# Configuration example
# Refer to the HCL Software Knowledge Base article KB0133342 for
# vendor-specific configuration values and version-matched guidance.