CVE-2025-53841 Overview
CVE-2025-53841 is a local privilege escalation vulnerability in the GC-AGENTS-SERVICE component of Akamai's Guardicore Platform Agent for Windows. The service attempts to load an OpenSSL configuration file (openssl.cnf) from a non-existent directory where standard Windows users hold default write permissions. An unprivileged local user can plant a crafted configuration file that references a malicious DLL through an OpenSSL engine directive. When the service loads the configuration, it executes the attacker-supplied DLL under the agent's SYSTEM context. This grants full SYSTEM privileges on the affected host. The issue is classified under [CWE-829: Inclusion of Functionality from Untrusted Control Sphere].
Critical Impact
An authenticated local user can escalate from a standard Windows account to SYSTEM by planting a crafted openssl.cnf file and referencing a malicious DLL through an OpenSSL engine definition.
Affected Products
- Akamai Guardicore Platform Agent for Windows versions prior to v49.20.1
- Akamai Guardicore Platform Agent for Windows versions prior to v50.15.0
- Akamai Guardicore Platform Agent for Windows versions prior to v51.12.0 and v52.2.0
Discovery Timeline
- 2025-12-03 - CVE-2025-53841 published to NVD
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2025-53841
Vulnerability Analysis
The GC-AGENTS-SERVICE runs as a Windows service under the LocalSystem account. During execution, the service (or a bundled OpenSSL-linked binary) queries the OPENSSLDIR path to locate the default openssl.cnf configuration file. The compiled path resolves to a directory that does not exist by default on Windows and sits in a location where the Users group has implicit write access. This mismatch between the trusted code path and the untrusted filesystem location creates the escalation primitive.
OpenSSL configuration files support engine definitions that can reference arbitrary shared libraries. When OpenSSL parses a planted configuration, it loads the referenced DLL and calls its initialization routine within the caller's process. Because the caller is a SYSTEM service, the attacker-controlled DLL executes with SYSTEM privileges. Exploitation requires only local, authenticated access with no user interaction.
Root Cause
The root cause is untrusted search path behavior tied to OpenSSL's default configuration lookup. The Guardicore agent was built with an OPENSSLDIR pointing to a filesystem location that is neither pre-created nor access-controlled. Standard users can create the missing directory tree and populate it with a hostile configuration file, satisfying [CWE-829].
Attack Vector
A local unprivileged attacker performs the following steps. First, the attacker creates the missing directory referenced by the agent's OpenSSL build. Second, the attacker writes an openssl.cnf file that declares a custom engine and points the engine's dynamic_path to an attacker-controlled DLL. Third, the attacker triggers or waits for the GC-AGENTS-SERVICE to consume the configuration, at which point the malicious DLL executes as SYSTEM. No network access, no user interaction, and no existing elevated privileges are required.
Detailed exploitation mechanics are described in the Akamai Security Advisory CVE-2025-53841 and the Akamai Windows Agent Vulnerability Summary.
Detection Methods for CVE-2025-53841
Indicators of Compromise
- Presence of an openssl.cnf file within a user-writable directory referenced by the Guardicore agent's OPENSSLDIR path.
- Unexpected DLL files placed adjacent to a planted openssl.cnf, particularly ones loaded by GC-AGENTS-SERVICE.exe.
- New or modified directories created by non-administrative users that match the OpenSSL default configuration lookup path.
Detection Strategies
- Monitor for file creation events targeting the OpenSSL default configuration path from non-SYSTEM, non-administrator security identifiers.
- Alert on GC-AGENTS-SERVICE.exe loading unsigned or unexpected DLLs, especially from paths outside the agent's installation directory.
- Correlate service starts of the Guardicore agent with process image loads that originate from user-writable directories.
Monitoring Recommendations
- Enable Windows Sysmon Event ID 7 (Image Loaded) with filtering on GC-AGENTS-SERVICE.exe to surface abnormal DLL loads.
- Track Windows Security Event ID 4663 for write access to the OpenSSL configuration directory tree.
- Baseline the DLLs typically loaded by the Guardicore agent and flag deviations for review.
How to Mitigate CVE-2025-53841
Immediate Actions Required
- Upgrade the Guardicore Platform Agent for Windows to v49.20.1, v50.15.0, v51.12.0, v52.2.0, or later on all Windows endpoints.
- Inventory all Windows systems running the agent and prioritize multi-user hosts, jump servers, and terminal servers.
- Audit the OpenSSL configuration directory referenced by the vulnerable agent build and remove any planted files or DLLs.
Patch Information
Akamai has released fixed builds of the Guardicore Platform Agent. Refer to the Akamai Guardicore Changelog for release notes and the Akamai Windows Agent Vulnerability Summary for the authoritative list of remediated versions. Apply the earliest fixed version within the branch deployed in your environment.
Workarounds
- Pre-create the OpenSSL configuration directory referenced by the agent and restrict its ACL so that only SYSTEM and Administrators can write to it.
- Restrict interactive and remote logon rights on systems running the agent until patching is complete to reduce the local attacker surface.
- Deploy application control policies that block DLL loads by GC-AGENTS-SERVICE.exe from user-writable directories.
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
