CVE-2026-103297: 
NixOS 脆弱性の分析と軽減

CVE-2026-103297 is an Improper Verification of Cryptographic Signature vulnerability (CWE-347) in Adobe's CAI Content Credentials ecosystem, classified as a security feature bypass. It affects the Content Credentials Rust SDK (c2pa) through v0.90.15, C2PA Tool (c2patool) through v0.27.15, and Content Credentials JS SDK (c2pa-web) through v0.13.4. The vulnerability was published on October 13, 2026, with patches released the same day. It carries a CVSS v3.1 base score of 7.5 (High) (GitHub Advisory, Adobe Advisory).

The vulnerability stems from improper or absent verification of cryptographic signatures within the CAI Content Credentials libraries (CWE-347), which are used to embed and validate provenance metadata in digital media per the C2PA specification. An unauthenticated remote attacker can exploit this flaw by submitting crafted content that bypasses signature validation checks, effectively spoofing or forging content credentials. This maps to CAPEC-475 (Signature Spoofing by Improper Validation), meaning an attacker can present unsigned or maliciously signed content as if it were legitimately credentialed. No user interaction is required, and attack complexity is low, making the vulnerability straightforward to exploit over the network (GitHub Advisory, Adobe Advisory).

Successful exploitation allows an unauthenticated attacker to bypass the cryptographic integrity protections of the C2PA content credentials system, gaining unauthorized write access to protected content metadata. The primary impact is a high integrity loss — attackers could forge, alter, or inject false provenance information into digital media without detection, undermining trust in content authenticity systems. Confidentiality and availability are not directly impacted, but the ability to spoof content credentials could enable disinformation campaigns or fraudulent attribution of digital content at scale (GitHub Advisory, Adobe Advisory).

As of the time of disclosure, there is no public proof-of-concept exploit and no evidence of in-the-wild exploitation (Feedly). The vulnerability is marked as automatable (no user interaction required), which increases its potential for mass exploitation if a PoC becomes available. The EPSS score is approximately 0.459%, placing it in the 38th percentile for exploitation likelihood within 30 days. The vulnerability is not currently listed in the CISA Known Exploited Vulnerabilities (KEV) catalog, and no threat actor attribution has been reported (GitHub Advisory).

Adobe has released patched versions for all three affected components. Users should upgrade to the following fixed versions as soon as possible:

• Content Credentials Rust SDK (c2pa): upgrade to v0.91.1 or later
• C2PA Tool (c2patool): upgrade to v0.28.1 or later
• Content Credentials JS SDK (c2pa-web / @contentauth/c2pa-web): upgrade to v0.15.3 or later

No configuration-based workarounds have been published. Given the network-accessible nature of the vulnerability and its high integrity impact, immediate patching is strongly recommended (Adobe Advisory, GitHub Advisory).