Harmonyos EUVD-2025-17086

The CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H vector indicates network-based attack with HIGH complexity (AC:H), suggesting exploitation requires specific conditions or multi-step techniques but requires no privileges or user interaction. The High impact across all three categories (CIA triad fully compromised) elevates concern. However, without confirmed EPSS data, KEV/CISA status, or public proof-of-concept availability, the true exploitability remains unclear. The AC:H rating is a mitigating factor—this is not a trivial one-click exploit. Risk priority should account for: (1) whether arkweb is embedded in production systems handling untrusted Wasm code, (2) whether PoC/active exploitation exists, and (3) whether version patching is feasible. For organizations running arkweb in sandboxed contexts or not executing untrusted Wasm, risk is lower; for those processing arbitrary Wasm in security-sensitive contexts, this is critical.

An attacker hosts a malicious website containing carefully crafted WebAssembly code that throws exception types not properly captured by the arkweb v8 module's exception handling mechanism. When a victim visits the site using an arkweb-based browser or embedded WebView, the Wasm code executes and triggers an unhandled exception that bypasses the security boundary. Depending on the uncaught exception's nature, this could: (a) crash the rendering process, enabling denial of service; (b) expose memory contents or execution state in error messages (confidentiality breach); or (c) in worst case, trigger memory corruption if the exception handler improperly manages the call stack. The AC:H rating suggests the attacker must craft the Wasm module and exception type combination precisely, making this a targeted rather than mass-exploitation attack. No confirmed public PoC exists in provided data, but the specific nature of the vulnerability (exception type enumeration) suggests PoC development is feasible for researchers with V8 expertise.