CVE-2026-48338: Adobe ColdFusion Path Traversal Flaw

CVE-2026-48338 Overview

Adobe ColdFusion contains a path traversal vulnerability that allows an authenticated attacker on an adjacent network to read arbitrary files outside the intended access scope [CWE-22]. The flaw affects ColdFusion 2023 (through Update 21) and ColdFusion 2025 (through Update 10). Exploitation does not require user interaction and results in a scope change, meaning the impact extends beyond the vulnerable component. Successful exploitation exposes sensitive configuration files, credentials, and source code stored on the ColdFusion server.

Critical Impact
An attacker with low privileges on an adjacent network can read arbitrary files from the ColdFusion server, exposing configuration data, credentials, and application source code.

Affected Products

Adobe ColdFusion 2023 (base release through Update 21)
Adobe ColdFusion 2025 (base release through Update 10)
All intermediate update releases for both major versions

Discovery Timeline

2026-07-14 - CVE-2026-48338 published to the National Vulnerability Database
2026-07-16 - Last updated in NVD database

Technical Details for CVE-2026-48338

Vulnerability Analysis

The vulnerability stems from improper limitation of a pathname to a restricted directory within Adobe ColdFusion. An attacker supplies crafted input containing directory traversal sequences that the application fails to normalize or validate against an allow-list of permitted paths. The resulting file access occurs outside the intended web root or application sandbox, disclosing arbitrary file content to the attacker.

The issue is classified under CWE-22, Improper Limitation of a Pathname to a Restricted Directory. The scope change indicated in the CVSS vector reflects that the vulnerable ColdFusion component can access resources managed by other security authorities on the host, such as operating system files outside the ColdFusion installation directory.

While confidentiality impact is high, the vulnerability does not permit modification of files or disruption of service. It remains a valuable primitive for attackers seeking credentials, session tokens, or configuration data that enable follow-on attacks.

Root Cause

ColdFusion fails to sanitize user-controlled path components before resolving them against the file system. Traversal sequences such as ../ allow the resolved path to escape the intended directory boundary. The application then returns file contents without verifying that the target path resides within an authorized directory.

Attack Vector

Exploitation requires network adjacency and authenticated access with low privileges. An attacker on the same logical network segment sends a crafted request containing traversal sequences to a vulnerable ColdFusion endpoint. No user interaction is required. The server processes the path, resolves it outside the intended scope, and returns the target file contents to the attacker.

The vulnerability manifests through path handling logic in ColdFusion request processing. Refer to the Adobe ColdFusion Security Advisory APSB26-82 for vendor technical details.

Detection Methods for CVE-2026-48338

Indicators of Compromise

HTTP requests to ColdFusion endpoints containing encoded or plain directory traversal sequences such as ../, ..%2f, or ..%5c
Access log entries showing successful responses for requests targeting file paths outside the web root, including WEB-INF, lib, or system directories
Unusual read access to ColdFusion configuration files such as neo-security.xml, password.properties, or seed.properties
Requests originating from adjacent network segments targeting .cfm handlers with abnormal path parameters

Detection Strategies

Deploy web application firewall rules that block path traversal patterns in query strings, form fields, and URL paths targeting ColdFusion applications
Enable ColdFusion server logging at a verbosity that captures full request URIs and correlate against known-good path patterns
Baseline file access behavior on the ColdFusion server and alert on reads of sensitive configuration files by the ColdFusion process

Monitoring Recommendations

Monitor the ColdFusion Administrator and application endpoints for authenticated requests containing traversal metacharacters
Track file read operations performed by the ColdFusion service account against paths outside the standard installation and application directories
Alert on egress traffic patterns consistent with bulk file exfiltration following anomalous request activity

How to Mitigate CVE-2026-48338

Immediate Actions Required

Apply the Adobe security updates referenced in APSB26-82 to ColdFusion 2023 and ColdFusion 2025 installations
Inventory all ColdFusion instances and confirm patch level against the fixed updates published by Adobe
Restrict network access to ColdFusion Administrator and internal endpoints so that only trusted management hosts can reach them
Rotate any credentials, API keys, or secrets stored in files accessible to the ColdFusion process, assuming potential prior disclosure

Patch Information

Adobe published fixed updates for both affected release trains. Refer to the Adobe ColdFusion Security Advisory APSB26-82 for the exact update versions that remediate CVE-2026-48338. Administrators should apply the latest available update for ColdFusion 2023 and ColdFusion 2025.

Workarounds

Enforce the ColdFusion lockdown guide recommendations, including restrictive file system permissions on the ColdFusion installation directory
Deploy a web application firewall in front of ColdFusion with rules that reject requests containing directory traversal sequences
Segment ColdFusion servers so that adjacent network access is limited to a minimum set of trusted hosts, reducing exposure to the required attack vector
Disable or restrict access to unused ColdFusion features and endpoints that accept file path parameters

bash

# Example WAF rule concept to block traversal patterns targeting ColdFusion
# ModSecurity-style pseudo-rule for illustration
SecRule REQUEST_URI|ARGS "@rx (\.\./|\.\.%2f|\.\.%5c)" \
    "id:1002026,phase:2,deny,status:403,\
    msg:'Path traversal attempt against ColdFusion (CVE-2026-48338)'"