CVE-2026-76189: CAI Content Credentials DOS Vulnerability

CVE-2026-76189 Overview

CVE-2026-76189 affects Adobe Content Authenticity Initiative (CAI) Content Credentials. The flaw is an integer underflow (wrap or wraparound) vulnerability classified as [CWE-191]. An attacker with local access can trigger the underflow to crash the application, producing a denial-of-service condition. Exploitation does not require user interaction or authentication. The vulnerability impacts availability only; confidentiality and integrity are unaffected. Adobe published Security Advisory APSB26-110 to address the issue.

Critical Impact
Local attackers can crash CAI Content Credentials processing through crafted input that triggers integer wraparound, resulting in application termination and disruption of content provenance workflows.

Affected Products

Adobe CAI Content Credentials
Content Authenticity SDK components referenced in Adobe advisory APSB26-110
Applications embedding vulnerable versions of the CAI Content Credentials library

Discovery Timeline

2026-08-25 - CVE-2026-76189 published to the National Vulnerability Database
2026-08-26 - Last updated in NVD database

Technical Details for CVE-2026-76189

Vulnerability Analysis

The vulnerability resides in the parsing or size-computation logic of CAI Content Credentials. When the affected code performs arithmetic on an unsigned integer without validating operand bounds, a subtraction operation drops the value below zero. The result wraps to a large positive value.

Downstream logic then uses this wrapped value as a length, index, or allocation size. This causes out-of-bounds access, invalid memory operations, or allocator failures that terminate the process. The vulnerability affects availability only, with no path to code execution or information disclosure indicated in the vendor advisory.

Root Cause

The root cause is missing bounds validation before an unsigned integer subtraction, matching the [CWE-191] Integer Underflow pattern. The affected routine trusts attacker-influenced size or length fields embedded in Content Credentials manifests. When these fields produce a subtraction that crosses zero, the wrapped value propagates through parsing logic and destabilizes the process.

Attack Vector

Exploitation requires local access to a system running CAI Content Credentials. An attacker supplies a crafted asset or manifest containing malformed size or offset fields. When the application processes the file, the underflow triggers and the application crashes. No privileges or user interaction are required to invoke the vulnerable code path.

No public proof-of-concept exploit is available at time of publication. Verified exploit code is not provided; refer to the Adobe Security Advisory APSB26-110 for vendor technical details.

Detection Methods for CVE-2026-76189

Indicators of Compromise

Repeated unexpected termination of processes that parse or verify Content Credentials manifests
Crash dumps referencing the CAI Content Credentials SDK with access violations near size-computation routines
Malformed C2PA or Content Credentials assets staged in user-writable directories or shared workflows

Detection Strategies

Monitor application crash telemetry and Windows Error Reporting or macOS crash reports for the affected binaries
Ingest process termination events into your SIEM and alert on abnormal crash frequency for content-processing hosts
Review file-parsing pipelines for anomalous asset inputs preceding process termination

Monitoring Recommendations

Track version inventories for CAI Content Credentials components across endpoints and build systems
Correlate file-open events on media assets with subsequent process crashes to identify triggering samples
Retain crash artifacts for forensic review to confirm the underflow signature described in APSB26-110

How to Mitigate CVE-2026-76189

Immediate Actions Required

Apply the updates described in Adobe Security Advisory APSB26-110 on all systems using CAI Content Credentials
Inventory applications and SDK integrations that embed the Content Authenticity library and prioritize patching
Restrict local access to systems processing untrusted Content Credentials assets until updates are deployed

Patch Information

Adobe addressed CVE-2026-76189 in the update referenced by advisory APSB26-110. Administrators should consult the Adobe Security Advisory APSB26-110 for fixed version numbers and download locations for the Content Authenticity SDK and affected products.

Workarounds

Avoid processing Content Credentials manifests from untrusted sources until patches are applied
Isolate content-processing workloads to non-privileged accounts and restricted directories
Implement file-format validation at ingest boundaries to reject malformed manifests before they reach the SDK

bash

# Verify installed Content Authenticity SDK version and compare to APSB26-110 fixed release
# Example inventory check - adapt to your deployment
find / -name "*c2pa*" -o -name "*content-credentials*" 2>/dev/null