CVE-2019-25355: gSOAP 2.8 Path Traversal Vulnerability

CVE-2019-25355 Overview

CVE-2019-25355 is a directory traversal vulnerability affecting gSOAP 2.8, a widely-used C/C++ toolkit for developing XML Web services and XML data bindings. This vulnerability allows unauthenticated attackers to access sensitive system files by manipulating HTTP path traversal techniques. Attackers can retrieve critical files such as /etc/passwd by sending crafted GET requests containing multiple ../ directory traversal sequences.

Critical Impact

Unauthenticated remote attackers can read arbitrary files from the server's filesystem, potentially exposing sensitive configuration files, credentials, and system information.

Affected Products

• gSOAP 2.8

Discovery Timeline

• 2026-02-18 - CVE CVE-2019-25355 published to NVD
• 2026-02-19 - Last updated in NVD database

Technical Details for CVE-2019-25355

Vulnerability Analysis

This vulnerability is classified as CWE-22 (Improper Limitation of a Pathname to a Restricted Directory), commonly known as Path Traversal or Directory Traversal. The flaw exists in how gSOAP 2.8 processes HTTP requests, failing to properly sanitize user-supplied input in file path parameters.

When gSOAP receives HTTP GET requests, it does not adequately validate or neutralize special elements within the requested path. This allows attackers to use directory traversal sequences (../) to escape the intended web root directory and access files anywhere on the filesystem that the web service process has read permissions for.

The network-based attack vector with no authentication required makes this vulnerability particularly dangerous for internet-facing deployments. Successful exploitation grants attackers read access to sensitive system files, potentially leading to credential theft, reconnaissance for further attacks, or exposure of confidential business data.

Root Cause

The root cause of this vulnerability lies in insufficient input validation and path canonicalization in gSOAP's HTTP request handling code. The library fails to properly sanitize or reject path components containing directory traversal sequences before using them to construct filesystem paths. This allows the ../ sequence to be processed literally, enabling attackers to navigate up the directory tree beyond the intended document root.

Attack Vector

The attack is executed remotely over the network without requiring any authentication. An attacker sends specially crafted HTTP GET requests to a gSOAP-based web service. By including multiple ../ sequences in the request path, the attacker can traverse directories upward from the web root and access arbitrary files on the system.

For example, a request targeting /etc/passwd would include enough ../ sequences to reach the root filesystem from wherever the web service's document root is located. The exact number of traversal sequences needed depends on the depth of the document root directory.

Technical details and proof-of-concept information are available in the Exploit-DB #47653 entry. Additional information can be found in the VulnCheck Advisory for Genivia.

Detection Methods for CVE-2019-25355

Indicators of Compromise

• HTTP access logs containing requests with multiple ../ sequences or encoded variants (%2e%2e%2f)
• Unusual file access patterns targeting sensitive system files like /etc/passwd, /etc/shadow, or configuration files
• GET requests attempting to access paths outside the normal application directory structure
• Web server error logs showing attempts to access files in unexpected filesystem locations

Detection Strategies

• Implement web application firewall (WAF) rules to detect and block requests containing directory traversal patterns
• Configure intrusion detection systems (IDS) to alert on HTTP requests with path traversal sequences
• Enable detailed access logging and monitor for requests targeting sensitive file paths
• Deploy endpoint detection and response (EDR) solutions to monitor for unauthorized file access by web service processes

Monitoring Recommendations

• Monitor HTTP request logs for anomalous path patterns including .., %2e%2e, and similar encoded sequences
• Set up alerts for any web service process attempting to read files outside its designated directory
• Implement file integrity monitoring on sensitive system files to detect unauthorized access
• Review and correlate access logs across multiple systems to identify potential exploitation campaigns

How to Mitigate CVE-2019-25355

Immediate Actions Required

• Audit all systems running gSOAP 2.8 to identify vulnerable deployments
• Implement network-level controls to restrict access to affected services from untrusted networks
• Deploy web application firewall rules to block directory traversal attempts
• Consider temporarily disabling affected web services until patches can be applied
• Review access logs for signs of prior exploitation

Patch Information

Organizations should consult Genivia for the latest security updates and patched versions of gSOAP. Review the Genivia Products Overview for current version information and upgrade paths. Apply vendor-supplied patches as soon as they become available.

Workarounds

• Implement strict input validation at the application layer to reject requests containing ../ sequences
• Deploy a reverse proxy or web application firewall in front of gSOAP services to filter malicious requests
• Restrict the web service process to run with minimal filesystem permissions using chroot or container isolation
• Use network segmentation to limit which systems can connect to vulnerable services
• Enable SELinux or AppArmor policies to restrict file access by the web service process

# Example WAF rule to block directory traversal attempts (ModSecurity syntax)
SecRule REQUEST_URI "\.\./" "id:1001,phase:1,deny,status:403,msg:'Directory traversal attempt detected'"
SecRule REQUEST_URI "%2e%2e%2f" "id:1002,phase:1,deny,status:403,msg:'Encoded directory traversal attempt detected'"