CVE-2026-67979: NASA cFS RCE Vulnerability

CVE-2026-67979 Overview

CVE-2026-67979 is an incorrect access control vulnerability in the Executive Services (ES) dynamic application start path component of NASA Core Flight System (cFS) version 7.0.1. Attackers can execute arbitrary code by placing a shared object on target storage that the flight software subsequently loads. The flaw is categorized under [CWE-284: Improper Access Control] and affects a framework widely used in spaceflight and embedded mission systems. Because cFS dynamically loads applications at runtime, an attacker who can write to the application path can achieve arbitrary code execution within the flight software context.

Critical Impact
Attackers can execute arbitrary code on cFS-based systems by dropping a malicious shared object onto storage read by the Executive Services loader.

Affected Products

NASA cFS (Core Flight System) v7.0.1
Executive Services (ES) dynamic application loader component
Embedded and spaceflight systems built on the affected cFS release

Discovery Timeline

2026-08-04 - CVE-2026-67979 published to the National Vulnerability Database
2026-08-05 - Last updated in NVD database

Technical Details for CVE-2026-67979

Vulnerability Analysis

NASA cFS provides a modular flight software framework in which the Executive Services subsystem manages application lifecycle, including loading applications dynamically from disk. In version 7.0.1, the dynamic application start path does not enforce sufficient access controls on the shared object files it loads. An attacker who can write a shared object to the path that Executive Services scans can cause the loader to map and execute attacker-controlled code within the cFS process. The result is arbitrary code execution with the privileges of the flight software runtime, undermining the isolation model between mission applications and the core framework.

Root Cause

The root cause is improper access control [CWE-284] on the dynamic application start path. Executive Services trusts the contents and origin of shared objects present on the configured storage location without verifying that the file was authored, signed, or authorized by a trusted source. Any write access to the load path becomes equivalent to code execution.

Attack Vector

Exploitation requires the attacker to place a crafted shared object on the storage location the cFS Executive Services loader reads. When Executive Services processes the dynamic application start path, it loads the attacker's shared object and transfers control to code inside it. See the GitHub cFS Issue Report for reported technical details.

No verified public exploit code is available for CVE-2026-67979. The vulnerability is described in prose only; refer to the upstream issue tracker for reproduction details.

Detection Methods for CVE-2026-67979

Indicators of Compromise

Unexpected shared object (.so) files appearing in the cFS Executive Services application load directory
Executive Services log entries showing application load events for applications not present in the approved mission manifest
File modifications to the dynamic application start path from processes or users outside the flight software build pipeline

Detection Strategies

Baseline the contents of the cFS application load path and alert on any deviation, including new, modified, or renamed shared objects
Correlate Executive Services ES_StartApp or equivalent load events against the authorized application inventory
Monitor filesystem write activity to the cFS storage location and flag writes originating from non-build, non-operator identities

Monitoring Recommendations

Forward cFS Executive Services logs and host filesystem telemetry to a central analytics platform for retention and correlation
Track process ancestry for any binary that writes to the dynamic application start path
Review Executive Services startup summaries after each boot to confirm only expected applications were loaded

How to Mitigate CVE-2026-67979

Immediate Actions Required

Restrict filesystem permissions on the cFS Executive Services dynamic application start path so only the build and deployment identity can write to it
Inventory all shared objects currently present in the load path and remove any that are not part of the approved mission build
Audit access to the target storage medium, including remote upload channels used to stage flight software updates

Patch Information

No fixed version is listed in the NVD entry for CVE-2026-67979 at the time of publication. Track the upstream GitHub cFS Issue Report for remediation status and apply any NASA-issued updates to cFS as they become available.

Workarounds

Mount the Executive Services application directory read-only during runtime, remounting read-write only for authenticated update procedures
Require cryptographic signature verification of shared objects before Executive Services is permitted to load them, implemented as a wrapper or build-time control
Segment operator and payload interfaces from the flight software filesystem so untrusted inputs cannot reach the dynamic application start path

bash

# Configuration example: restrict write access to the cFS application load path
chown root:cfs /cf/apps
chmod 750 /cf/apps
mount -o remount,ro /cf