CVE-2026-6505: ACAP Framework Privilege Escalation Flaw

CVE-2026-6505 Overview

CVE-2026-6505 is a Time-of-Check to Time-of-Use (TOCTOU) race condition in the AXIS Camera Application Platform (ACAP) framework. The flaw resides in the interval between when the framework validates a resource and when it uses that resource. An attacker who wins the race can elevate privileges on the affected Axis device. Exploitation requires the device to be configured to allow installation of unsigned ACAP applications, and the victim must be convinced to install a malicious ACAP application. The vulnerability is tracked under CWE-367.

Critical Impact
Successful exploitation allows a local attacker to escalate privileges on the Axis device by racing the ACAP framework's validation logic through a malicious ACAP application.

Affected Products

Axis devices running the ACAP framework
Devices configured to allow installation of unsigned ACAP applications
Refer to the Axis Security Advisory CVE-2026-6505 for the authoritative list of affected firmware versions

Discovery Timeline

2026-08-11 - CVE-2026-6505 published to the National Vulnerability Database
2026-08-11 - Last updated in NVD database

Technical Details for CVE-2026-6505

Vulnerability Analysis

The ACAP framework validates an attribute or state of a shared resource and then acts on that resource without ensuring the state remains unchanged. In this window, a malicious ACAP application can substitute or modify the resource so the framework operates on attacker-controlled data. Because the framework runs with elevated privileges relative to installed applications, the substitution grants the attacker access to operations reserved for higher-privileged contexts.

Exploitation is bounded by several conditions. The device owner must first disable signature enforcement to permit unsigned ACAP applications. The attacker must then deliver a malicious application and persuade the operator to install it. Once installed, the application can repeatedly attempt to win the race and trigger the privileged code path.

Root Cause

The root cause is non-atomic handling of a security-sensitive check and its subsequent use, classified as CWE-367: Time-of-Check Time-of-Use Race Condition. The framework lacks a lock, atomic operation, or handle-based reference that would guarantee the checked resource is identical to the resource ultimately used.

Attack Vector

The attack vector is local and requires high privileges plus user interaction. A malicious ACAP application, once installed on a device that permits unsigned applications, races the framework's validation window to escalate its own privileges on the Axis device. No remote or network path to exploitation exists without the prior installation step.

No public proof-of-concept code is available. See the Axis Security Advisory CVE-2026-6505 for vendor technical details.

Detection Methods for CVE-2026-6505

Indicators of Compromise

Presence of unsigned or untrusted ACAP applications installed on Axis devices
Configuration flag permitting installation of unsigned ACAP applications set to enabled
Unexpected processes or files created by an ACAP application outside its designated sandbox directory
Anomalous privilege transitions or root-owned artifacts originating from an application context

Detection Strategies

Audit device inventories for firmware versions listed in the Axis advisory and flag devices that allow unsigned application installation
Compare installed ACAP application signatures and package hashes against an approved allowlist
Monitor Axis device syslog output for repeated failed installation attempts or unusual application lifecycle events indicative of race exploitation attempts

Monitoring Recommendations

Forward Axis device syslog to a centralized logging platform and alert on ACAP install, upgrade, and privilege events
Track configuration drift on the AllowUnsignedPackages setting or its equivalent across the device fleet
Correlate device management API calls with the identity of the operator authorizing new ACAP installations

How to Mitigate CVE-2026-6505

Immediate Actions Required

Disable installation of unsigned ACAP applications on all Axis devices unless a documented business need requires it
Inventory currently installed ACAP applications and remove any that are unsigned or not sourced from a trusted publisher
Apply the firmware update referenced in the Axis Security Advisory CVE-2026-6505 once available for the affected model
Restrict administrative access to Axis devices to a limited set of operators and enforce multi-factor authentication on management interfaces

Patch Information

Axis Communications has published a security advisory for CVE-2026-6505 that identifies affected firmware and lists remediated versions. Consult the Axis Security Advisory CVE-2026-6505 for model-specific patched firmware and upgrade procedures.

Workarounds

Enforce signed-application-only mode on every Axis device to eliminate the primary precondition for exploitation
Segment Axis devices onto a management VLAN and block outbound internet access to prevent delivery of malicious ACAP packages
Require change-control approval for any ACAP application installation and validate publisher signatures before deployment

bash

# Configuration example: query and enforce signed-application policy via the Axis VAPIX API
# Replace <device>, <user>, and <password> with environment-specific values

# Check current unsigned-package policy
curl -u <user>:<password> \
  "https://<device>/axis-cgi/param.cgi?action=list&group=Network.ACAP.AllowUnsignedPackages"

# Disable installation of unsigned ACAP applications
curl -u <user>:<password> \
  "https://<device>/axis-cgi/param.cgi?action=update&Network.ACAP.AllowUnsignedPackages=no"