CVE-2026-100138: CAI Content Credentials DOS Vulnerability

CVE-2026-100138 Overview

CVE-2026-100138 is an uncontrolled resource consumption vulnerability [CWE-400] affecting Adobe's Content Authenticity Initiative (CAI) Content Credentials. An unauthenticated remote attacker can exploit the flaw to exhaust system resources and trigger an application denial-of-service condition. Exploitation requires no user interaction and no privileges, making the attack surface broad for any service exposing the vulnerable component to the network.

Adobe disclosed the issue in security advisory APSB26-163. The vulnerability impacts availability only; confidentiality and integrity of application data are not affected. Organizations consuming or embedding the CAI Content Credentials SDK should treat this as a priority availability risk for any publicly reachable endpoint.

Critical Impact
Unauthenticated network attackers can crash or hang services relying on CAI Content Credentials, interrupting content provenance workflows and dependent applications.

Affected Products

Adobe CAI Content Credentials SDK (see Adobe advisory APSB26-163 for specific affected versions)
Applications and services embedding the vulnerable Content Credentials component
Content provenance and signing pipelines that process untrusted input through the SDK

Discovery Timeline

2026-10-13 - CVE-2026-100138 published to the National Vulnerability Database (NVD)
2026-10-14 - Last updated in NVD database

Technical Details for CVE-2026-100138

Vulnerability Analysis

The vulnerability stems from uncontrolled resource consumption inside the CAI Content Credentials parsing or verification path. An attacker submits crafted input that forces the application to allocate memory, consume CPU cycles, or spawn processing work disproportionate to the input size. Repeated or single-shot delivery of such input exhausts available resources and causes the application to stop servicing legitimate requests.

Because the attack vector is network-based and requires neither authentication nor user interaction, any exposed endpoint that accepts files or metadata processed by the SDK is reachable by remote adversaries. The CVSS vector reports no impact to confidentiality or integrity, confirming the issue is strictly an availability flaw.

The EPSS score of 0.636% places this vulnerability in a moderate exploitation-likelihood band for the near term. No public proof-of-concept or in-the-wild exploitation has been documented at the time of publication.

Root Cause

The root cause maps to [CWE-400] Uncontrolled Resource Consumption. The affected code path lacks adequate limits on memory allocation, iteration counts, or processing time when handling attacker-controlled Content Credentials data. Without upstream bounds checks or quotas, malformed or maliciously structured inputs force the component into an unbounded workload.

Attack Vector

An attacker crafts a Content Credentials payload that triggers excessive resource usage during ingestion or verification. The payload is delivered over the network to any application endpoint that passes attacker-supplied data to the vulnerable SDK, including upload handlers, media verification services, and asset ingestion pipelines. Successful exploitation renders the application unresponsive until resources are reclaimed or the process is restarted.

No verified exploit code is available. Refer to the Adobe Security Advisory APSB26-163 for vendor technical details.

Detection Methods for CVE-2026-100138

Indicators of Compromise

Sudden spikes in CPU or memory utilization on hosts running CAI Content Credentials processing workloads
Application process restarts, out-of-memory kills, or watchdog timeouts correlated with inbound Content Credentials requests
Repeated requests from the same source containing anomalously large or malformed Content Credentials payloads

Detection Strategies

Baseline normal resource usage of services that invoke the CAI SDK and alert on sustained deviations
Inspect reverse proxy and application logs for request bodies containing Content Credentials manifests exceeding expected size thresholds
Correlate availability-impacting events (503 responses, pod evictions, container OOM kills) with network traffic to Content Credentials endpoints

Monitoring Recommendations

Enable per-process resource accounting and ingest metrics into a central observability or SIEM platform
Track request rate, payload size distribution, and processing latency for endpoints that accept provenance data
Alert on repeated client-side disconnects or timeouts that indicate server-side resource exhaustion

How to Mitigate CVE-2026-100138

Immediate Actions Required

Review Adobe Security Advisory APSB26-163 and apply the fixed SDK version to all affected deployments
Inventory applications and pipelines that embed CAI Content Credentials and prioritize network-exposed instances
Restrict exposure of Content Credentials ingestion endpoints to trusted networks until patching is complete

Patch Information

Adobe addresses CVE-2026-100138 in the updated CAI Content Credentials SDK release documented in advisory APSB26-163. Rebuild and redeploy all applications that statically link or bundle the SDK after upgrading. Verify the deployed version using your package manager or build manifest.

Workarounds

Enforce request size limits and timeouts at the reverse proxy or API gateway for endpoints that process Content Credentials
Apply rate limiting and client reputation controls to reduce the volume of attacker-controlled inputs reaching the SDK
Isolate Content Credentials processing in dedicated workers with cgroup memory and CPU quotas to contain exhaustion

bash

# Example nginx limits for a Content Credentials ingestion endpoint
client_max_body_size 5m;
client_body_timeout 10s;
limit_req_zone $binary_remote_addr zone=cai:10m rate=10r/s;

location /verify {
    limit_req zone=cai burst=20 nodelay;
    proxy_read_timeout 15s;
    proxy_pass http://cai_backend;
}