Zero-Click Mobile Security Exploitation

Submission Type Vulnerability Disclosure / Bug Bounty Submission Submission Category Mobile Security — Zero-Click Exploitation Severity Classification Critical (CVSS 9.0–10.0) 1. Submission Summary This submission describes a discovered zero-click attack chain affecting mobile messaging applications on both iOS and Android platforms. The vulnerability allows an attacker to compromise a target device without any user interaction. This document serves as the formal description for researchers, security teams, and bug bounty programs to evaluate, reproduce, and remediate the reported issue. Submitted by: [Researcher Name / Handle] Contact: [Secure Email / PGP Key] Date of Discovery: [Date] Disclosure Type: Coordinated / Responsible Disclosure 2. Vulnerability Overview What was found: A chain of vulnerabilities enabling zero-click remote code execution on mobile devices through a messaging application. Where it was found: Mobile messaging client on iOS and Android How it was found: [Fuzzing / Static analysis / Manual code review / Traffic analysis / Reverse engineering] Why it matters: An attacker can compromise a target device with no user interaction — no clicks, no downloads, no prompts. The victim only needs to receive a message. 3. Affected Platforms and Versions Platform Application Version OS Version Status iOS [Version range] [iOS range] Confirmed vulnerable Android [Version range] [Android range] Confirmed vulnerable Patch Status: [Unpatched / Partially patched / Patched in version X] 4. Vulnerability Details 4.1 Root Cause Describe the underlying flaw: Type: [Memory corruption / Logic flaw / Command injection / Deserialization / Authorization bypass] Component: [Media parser / Session handler / URL scheme handler / AI content pipeline] Trigger: [Malicious message / Auto-downloaded media / Linked-device sync / AI-generated response] 4.2 Attack Chain Describe the chain of events: Initial vector: Attacker sends a crafted message to target Processing flaw: Client processes the message without validation Privilege escalation: Attacker gains code execution or session access Persistence: Attacker maintains access via [linked device / background process / scheduled task] 4.3 Platform Differences Aspect iOS Android Trigger mechanism [Describe] [Describe] Exploited component [Describe] [Describe] Blocking protections [Lockdown Mode, BlastDoor] [Scoped Storage, SELinux] Exploit reliability [High/Medium/Low] [High/Medium/Low] 5. Prerequisites For the attack to succeed, the following conditions must be met: □ Target uses affected app version □ Target runs affected OS version □ Auto-download enabled (if applicable) □ Target is in a group with attacker (if applicable) □ Linked-device feature active (if applicable) □ Specific network conditions (if applicable) Minimum requirements: [List the absolute minimum conditions] 6. Proof of Concept Important: Provide only enough to demonstrate the vulnerability. Do not weaponize. 6.1 Reproduction Steps (High-Level) [Step 1 — setup] [Step 2 — trigger] [Step 3 — observe] [Step 4 — confirm compromise] 6.2 Evidence Collected □ Crash logs □ Memory dumps □ Network captures □ Screenshots / video □ Log excerpts (unified logs / logcat) 6.3 Indicators of Compromise Indicator Platform Description [Log event] iOS [Description] [File artifact] Android [Description] [Network signature] Both [Description] 7. Impact Assessment 7.1 Technical Impact Confidentiality: [Full device access / Message access / Contact access] Integrity: [Code execution / Message tampering / Session hijack] Availability: [Device bricking / App crash / Data loss] 7.2 Realistic Attack Scenarios Targeted surveillance: High-value individuals (journalists, activists, executives) Mass exploitation: If trigger is broadcastable Supply chain: If exploited via shared content 7.3 Severity Justification CVSS Score: [X.X] Vector: [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H] Rationale: Zero-click, remote, cross-platform, high impact 8. Reproduction Environment Item Details Test device 1 [iPhone model, iOS version] Test device 2 [Android model, OS version] App version [Version tested] Network setup [Wi-Fi / Cellular / Isolated] Tools used [Frida / LLDB / Wireshark / etc.] 9. Detection Guidance for Defenders 9.1 iOS Detection Unified log queries: [Provide specific predicates] sysdiagnose indicators: [List artifacts] Linked-device audit: [How to check for rogue sessions] 9.2 Android Detection logcat queries: [Provide specific filters] File system artifacts: [Paths to check] Permission audit: [What to review] 9.3 Network Detection C2 patterns: [URLs, headers, timing] Beacon behavior: [Interval, size, destination] Anomalous traffic: [What stands out] 10. Mitigation Recommendations 10.1 Immediate (User-Level) Disable auto-download for all media types Restrict group additions to contacts only Enable two-step verification Audit linked devices and remove unknown sessions Enable iOS Lockdown Mode (high-risk users) Restrict Android app permissions 10.2 Short-Term (Vendor-Level) Patch the vulnerable component Add input validation for the trigger vector Sandbox the affected parser Enforce authentication on session sync 10.3 Long-Term (Platform-Level) Strengthen sandboxing for media parsers Add memory safety protections (e.g., PAC, MTE) Improve AI content pipeline validation Expand detection telemetry for zero-click vectors 11. Disclosure Timeline Date Event [Date] Vulnerability discovered [Date] Initial report submitted to vendor [Date] Vendor acknowledged receipt [Date] Vendor requested additional details [Date] Patch released [Date] Public disclosure Disclosure Window: [90 days / Extended / Coordinated] 12. Submission Checklist Before submitting, confirm: □ All affected platforms and versions documented □ Root cause clearly explained □ Reproduction steps provided (non-weaponized) □ Impact assessment completed □ Detection guidance included □ Mitigation recommendations provided □ Ethical boundaries respected (no exploit c