Content Credentials SDK EUVD-2026-100736

Exploitation requires that the target application use the CAI Content Credentials SDK's signature-verification path as a trust/authorization decision - i.e. the SDK must be invoked to validate a signed credential or manifest whose authenticity gates write access or provenance trust. Per the CVSS vector (AV:N/AC:L/PR:N/UI:N), no authentication, no user interaction, and only low attack complexity are needed against an exposed verification endpoint. The practical limiting factor is deployment-dependent: systems that merely display Content Credentials informationally, or that do not rely on the SDK's verification result for security decisions, are far less exposed than those enforcing access or trust based on it. Exact vulnerable SDK versions were not provided, so defenders must confirm their integrated SDK version against Adobe APSB26-163.

The CVSS 3.1 vector (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N, base 7.5) describes a network-reachable, low-complexity, unauthenticated flaw with no user interaction and a pure integrity impact (I:H, C:N, A:N) - consistent with a cryptographic signature-verification bypass (CWE-347) in the CAI Content Credentials SDK. No EPSS score, CISA KEV listing, SSVC decision data, or public POC was provided in the input, so there is no public exploit identified at time of analysis and no evidence of active exploitation. This is therefore a high-severity-by-CVSS issue whose real-world urgency cannot be fully ranked without exploitation-probability data: the impact is serious where the SDK is used as a trust boundary (accepting forged/altered content provenance as valid), but exploitation value depends heavily on whether a given deployment relies on Content Credentials for security decisions. The vendor CVSS vector and description are internally consistent (both point to remote, unauthenticated integrity compromise); the only conflict is between a high integrity score and the absence of confidentiality/availability impact, which is expected for a signature-bypass bug. Treat as a priority for any system that enforces trust based on Content Credentials, but note the missing EPSS/KEV signals mean widespread opportunistic exploitation is unproven.

An attacker crafts content (or a JWT/credential manifest) with a forged or manipulated cryptographic signature and submits it to a service that uses the CAI Content Credentials SDK to verify provenance. Because the SDK improperly verifies the signature, the forged credential is accepted as authentic, letting the attacker assert trusted content provenance or obtain unauthorized write access without authentication or user interaction. No public proof-of-concept was provided in the available data.