CVE-2026-47903: Adobe CAI Content Credentials Input Validation DoS Vulnerability

Technical summary

CVE-2026-47903 is an improper input validation vulnerability (CWE-20) in Adobe's Content Authenticity Initiative (CAI) implementation. The flaw allows unauthenticated, unauthenticated attackers to trigger an application crash by supplying malformed or unexpected input to c2pa-web or c2pa library versions up to and including 0.7.1 and 0.80.1 respectively. The local attack vector and lack of prerequisites indicate the vulnerability is reachable in typical deployment scenarios, though the impact is limited to availability (crash), with no confidentiality or integrity compromise.

Business impact

Organizations deploying c2pa for content authentication workflows face service disruption risk. A successful denial-of-service attack could interrupt content verification pipelines, impact user-facing authentication features, and degrade service availability. For media and publishing platforms relying on CAI for provenance verification, this could undermine trust in content authenticity checks. The medium severity reflects the availability-only impact; however, repeated DoS attacks could have cumulative operational consequences.

Affected systems

Adobe c2pa library (version 0.80.1 and earlier) and c2pa-web package (version 0.7.1 and earlier) are affected. This includes any application or service that integrates these libraries, particularly web applications using c2pa-web for client-side content verification, and backend systems using the c2pa library for authentication workflows. Organizations should inventory all internal and third-party integrations of these components.

Exploitability

Exploitability is straightforward due to the local attack vector, lack of authentication requirements, and no user interaction needed. However, practical exploitation depends on whether the affected component is network-exposed or accessible to untrusted input sources. Applications that accept untrusted c2pa data for processing (e.g., uploaded manifests, external content metadata) face direct risk. The vulnerability is not currently tracked in CISA's Known Exploited Vulnerabilities catalog, but the low barrier to exploitation warrants rapid assessment and patching.

Remediation

Upgrade c2pa-web to a version beyond 0.7.1 and c2pa to a version beyond 0.80.1. Verify compatibility with your application stack and test thoroughly in a staging environment before production deployment. If immediate patching is not feasible, consider implementing network-level or application-level input validation to reject malformed c2pa data structures and limit exposure to untrusted sources.

Patch guidance

Consult Adobe's official security advisories for specific patch version numbers and compatibility notes. Patches are expected to be available for both npm (c2pa-web) and the core c2pa library. Establish a staged rollout: first test in development, then staging with real-world content samples, then production. Monitor logs for any input validation errors or crashes during and after deployment to confirm remediation effectiveness.

Detection guidance

Monitor application logs and error reporting for repeated crashes or exceptions originating from c2pa input parsing. Watch for HTTP 500 errors, segmentation faults, or unexpected process terminations correlated with c2pa library calls. Implement input validation upstream of c2pa to catch obviously malformed data. Threat hunters should review authentication flow logs and content verification pipeline metrics for anomalous patterns indicative of DoS attempts.

Why prioritize this

Although severity is medium, the lack of authentication requirements and zero user interaction make this a high-priority patch candidate for systems that expose c2pa functionality to untrusted input. Prioritize systems handling user-uploaded content, external manifests, or API endpoints that consume c2pa data. Organizations with SLAs tied to content authentication availability should treat this as critical for their specific risk context.

Risk score, explained

The CVSS 3.1 score of 6.2 (MEDIUM) reflects a local attack vector with low complexity and no privileges required, resulting in high availability impact but no confidentiality or integrity loss. While the score is medium, the practical risk is elevated for web-facing or API-driven deployments that accept untrusted c2pa input, warranting treatment above the base score in threat modeling.

Frequently asked questions