CVE-2026-67105: HCLTech BigFix Information Disclosure Flaw

CVE-2026-67105 is an information disclosure vulnerability in HCLTech BigFix Service Management caused by insecure communication. Attackers with network access can intercept unencrypted traffic to extract sensitive data. This article covers technical details, affected versions, impact analysis, and mitigation strategies.

CVE-2026-67105 Overview

CVE-2026-67105 affects HCL BigFix Service Management and stems from insecure communication between backend services. The product transmits data over unencrypted HTTP channels, exposing traffic to interception by attackers with internal network access. An adversary positioned on the internal network can read sensitive data in transit and perform man-in-the-middle (MitM) attacks against backend communications. The weakness is classified under [CWE-319: Cleartext Transmission of Sensitive Information].

Critical Impact
Attackers with internal network access can intercept backend HTTP traffic, extract sensitive data, and manipulate requests through MitM attacks against HCL BigFix Service Management.

Affected Products

HCL BigFix Service Management version 27
Deployments relying on unencrypted inter-service HTTP communication
Environments where backend components share untrusted internal network segments

Discovery Timeline

2026-10-01 - CVE-2026-67105 published to NVD
2026-10-05 - Last updated in NVD database

Technical Details for CVE-2026-67105

Vulnerability Analysis

HCL BigFix Service Management version 27 exchanges data between backend services over plaintext HTTP. Because the channel lacks transport-layer encryption, any party able to observe network traffic between those services can read request and response bodies in full. This includes session identifiers, API payloads, and other sensitive fields transmitted during normal operation.

The vulnerability enables two primary attack outcomes. First, passive attackers can harvest credentials and business data by sniffing traffic. Second, active attackers can inject or modify requests, altering application behavior or impersonating services. Successful exploitation requires access to the internal network path between backend components.

Root Cause

The root cause is the absence of TLS on inter-service communication paths. Backend components rely on HTTP rather than HTTPS, so sensitive data traverses the network without confidentiality or integrity protection. This design choice aligns with [CWE-319] and violates the principle of encrypting data in transit regardless of network trust assumptions.

Attack Vector

An attacker must have access to a network segment carrying backend HCL BigFix Service Management traffic. From that position, the attacker uses packet capture tools or ARP spoofing to intercept HTTP exchanges. Captured traffic yields sensitive data directly, while active interception allows request tampering and response injection. The attack vector is network-based and does not require authentication to the application.

No verified public proof-of-concept code is available at this time. Refer to the HCL Software Support Article for vendor-provided technical details.

Detection Methods for CVE-2026-67105

Indicators of Compromise

Unexpected HTTP (port 80 or non-TLS) traffic between HCL BigFix Service Management backend hosts
ARP table anomalies or duplicate MAC addresses on network segments carrying BigFix traffic
Unusual packet capture processes running on hosts adjacent to backend services
Session reuse or replayed request patterns observed in application logs

Detection Strategies

Inspect network flows for cleartext HTTP between BigFix Service Management components and alert on their presence
Deploy network intrusion detection signatures that identify HTTP requests to BigFix backend endpoints
Correlate authentication events with source IP changes that could indicate session hijacking via MitM

Monitoring Recommendations

Enable NetFlow or packet brokering on segments hosting BigFix backend services to baseline normal traffic
Monitor for new or unauthorized devices on management VLANs that carry BigFix traffic
Alert on configuration changes that disable TLS enforcement for backend endpoints

How to Mitigate CVE-2026-67105

Immediate Actions Required

Review the HCL Software Support Article and apply vendor-recommended remediation for version 27
Isolate HCL BigFix Service Management backend components onto a dedicated, restricted network segment
Restrict administrative and operational access to the network paths carrying backend traffic
Rotate credentials, API tokens, and session secrets that may have transited unencrypted channels

Patch Information

HCL has published guidance in support article KB0134015. Administrators should consult the vendor advisory for the fixed release and configuration changes required to enforce encrypted communication between backend services.

Workarounds

Enforce TLS on all backend service endpoints and disable plaintext HTTP listeners where possible
Place backend traffic inside an IPsec tunnel or mutually authenticated TLS proxy when native TLS is not available
Apply network segmentation and host firewalls to limit which systems can reach backend ports
Monitor for and block ARP spoofing using switch-level protections such as Dynamic ARP Inspection

bash

# Example: block cleartext HTTP to a BigFix backend port using iptables
iptables -A INPUT -p tcp --dport 80 -m comment \
  --comment "Block cleartext HTTP to BigFix backend" -j DROP

# Example: allow only TLS (443) from the application tier subnet
iptables -A INPUT -p tcp -s 10.20.30.0/24 --dport 443 -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -j DROP