CVE-2026-6935 in Concert
Summary
by MITRE • 09/24/2026
IBM Concert 1.0.0 through 3.0.0 invokes operating system commands without fully qualifying executable paths or adequately restricting search path resolution. As a result, an attacker with local system access can manipulate the search path environment to execute untrusted or malicious code.
If you want to get best quality of vulnerability data, you may have to visit VulDB.
Analysis
by VulDB Data Team • 09/24/2026
The vulnerability identified in IBM Concert versions 1.0.0 through 3.0.0 represents a critical flaw in how the application interacts with the underlying operating system for command execution tasks. This issue stems from an improper implementation of process creation mechanisms, specifically regarding the handling of executable paths and environment variables during runtime operations. When the software needs to invoke external commands or scripts, it fails to provide fully qualified absolute paths for these executables. Instead, it relies on the system's default search path resolution mechanism, which scans a series of directories listed in the PATH environment variable to locate the requested binary. This approach introduces significant ambiguity into the execution context because the operating system will execute whichever file matches the command name first within those searched directories.
From a technical perspective, this behavior constitutes an insecure dynamic link library or search path vulnerability. By not explicitly defining the absolute path of trusted binaries, IBM Concert inadvertently allows for potential manipulation by any user account that has local access to the system environment. An attacker with such access can modify the PATH variable prior to triggering the vulnerable function within IBM Concert. If a malicious executable is placed in one of the directories listed earlier in the search order than the legitimate binary, the operating system will prioritize and execute this untrusted code instead of the intended program. This technique effectively bypasses authentication controls because it does not require exploiting a buffer overflow or injection flaw; rather, it exploits the trust relationship between the application and its execution environment to achieve arbitrary code execution under the privileges of the user running IBM Concert.
The operational impact of this vulnerability is severe for any deployment where local system access can be obtained by unauthorized actors. If an attacker gains even basic shell access on a server hosting IBM Concert, they can escalate their privileges or pivot further into the network by executing malicious commands with the higher-level permissions associated with the application's process account. This could lead to complete compromise of the host machine, data exfiltration, installation of backdoors, or disruption of services. The risk is particularly acute in multi-tenant environments or shared hosting scenarios where multiple users have access to the same operating system instance but are expected to remain isolated from one another.
This flaw aligns with Common Weakness Enumeration (CWE) category CWE-427, which describes Uncontrolled Search Path Element. It also maps directly to MITRE ATT&CK technique T1059, specifically Command and Scripting Interpreter sub-techniques such as T1059.004 for Unix Shell Commands or T1059.006 for Python if applicable, depending on the specific implementation details of how IBM Concert invokes these commands. The attack vector is classified under Local Privilege Escalation because it requires initial local access but results in execution with elevated privileges inherent to the application's runtime context.
Mitigation strategies should focus on hardening the environment and updating software configurations where possible. Since this issue persists through version 3.0.0, applying any available patches or updates released by IBM that address path resolution is the primary remediation step. In cases where immediate patching is not feasible, administrators can implement mitigations at the operating system level. This includes restricting write permissions to directories listed in the PATH variable for non-administrative users, ensuring that only trusted binaries exist in those locations, and configuring strict environment variable policies via group policy or security modules like SELinux or AppArmor. Additionally, modifying IBM Concert's configuration to use absolute paths explicitly within its internal scripts or wrappers can reduce reliance on system search resolution, although this may require vendor assistance for implementation. Regular auditing of PATH variables and monitoring for unusual process executions originating from the application directory can also aid in early detection of exploitation attempts.