Threat reportVulnerabilityTL-2026-4434
AI-assisted reverse engineering (OpenAI Codex + Binary Ninja MCP) defeats encryption in NetacFileLock, SecZure YutianDun, KakaSoft USB Copy Protection and Nexcopy Copy Secure USB drive software
AI-assisted reverse engineering (OpenAI Codex + Binary Ninja (TL-2026-4434) is a medium-severity software vulnerability, first published 2026-10-26. It has no confirmed attribution, affects Netac NetacFileLock, maps to 7 MITRE ATT&CK techniques (T1005, T1025, T1078.001), and is covered by 9 detection rules and 14 indicators of compromise.
- Severity
- MEDIUMAssessed severity
- CVEs
- 0None referenced
- Techniques
- 7MITRE ATT&CK
- Actors
- 0Not attributed
- Detection rules
- 9SPL · KQL · Sigma
- IOCs
- 14Indicators of compromise
Key facts for TL-2026-4434
- Threat ID
- TL-2026-4434
- Severity
- MEDIUM
- Status
- TRACKING
- Category
- VULNERABILITY
- First published
- Last reviewed
- Attribution confidence
- LOW
- Motivation
- UNKNOWN
- Target sectors
- government administration, finance, health, technology, manufacturing
- Target regions
- Global
- Detection rules
- 9
- Indicators of compromise
- 14
Malware and tooling in AI-assisted reverse engineering (OpenAI Codex + Binary Ninja
Malware and tooling: Binary Ninja MCP, OpenAI Codex
How AI-assisted reverse engineering (OpenAI Codex + Binary Ninja works
Researcher Xusheng Li used an AI coding agent (referred to as Codex) driving Binary Ninja through its Model Context Protocol interface to reverse four USB drive encryption/copy-protection products in roughly 7-36 minutes each. The analysis recovered embedded fixed keys, built-in backdoor account passwords and weak key derivation that allow decryption without the user password. No CVEs, vendor responses or in-the-wild exploitation are reported.
On 2026-10-22 Xusheng Li published 'Breaking more encrypted USB drives with AI' on the Binary Ninja blog, extending earlier manual research (a time-travel-debugging talk and the Paged Out! issue 5 article 'Examining USB Copy Protection', November 2024). GBHackers covered it on 2026-10-26. An AI agent connected to Binary Ninja via MCP unpacked installers, recognised cryptographic code patterns, reverse engineered a custom hash function and recovered key material statically, including analysis of Windows binaries from macOS. The AI reproduced the earlier NetacFileLock finding in about 7 minutes and found new design flaws in three previously unanalysed products.
NetacFileLock: a fixed 32-byte AES-256 key is embedded in the executable; the user password is checked separately (MD5-based verification) and does not determine the encryption key. Files are encrypted ECB-style in 16-byte blocks with no IV or chaining, and in 'fast mode' only the first 1,024 bytes of supported formats (PNG, JPEG, GIF, TIFF, DWG, PSD, PST, DBX, Office, MDB, WPD, PDF, ZIP, RAR, WAV, AVI, RAM, RM, MPEG, MOV, ASF, MIDI) are encrypted. File signatures use unkeyed MD5, an SM4 option uses another fixed key, and passwords are written in plaintext to diagnostic logs.
SecZure YutianDun (AQUP): credentials are hashed with MD5 and keys wrapped with HMAC-MD5, with AES-128 in ECB mode for file encryption. Each AES key uses 16 hex characters, capping entropy at 64 bits. Three accounts can unwrap the content identifier and decrypt files: Buffer/123456, System/SECZURE.COM (the primary post spells it SERZURE.COM in one place; sources disagree) and the administrator with a user-set password. The built-in accounts bypass the user password entirely.
KakaSoft USB Copy Protection 5.6.0.299: the Normal setting only hides/locks files with no encryption. High XORs the first 16,385 bytes with a single-byte key (256 possibilities; known file signatures reveal it). Highest uses 256-bit Blowfish (layout: 8-byte salt, 8-byte IV, ciphertext, 75-byte trailer) but the key derives from a modified MD5 (altered round-three rotation counts 4,11,16,16,4,11,11,4 and permuted hex alphabet 1903642857ACBEDF) of an embedded fixed seed plus RIPEMD-128(salt || internal password), enabling passwordless decryption. Files are hidden in an obfuscated exFAT tree using reserved device names (COM1) and Unicode private-use characters (U+E347).
Nexcopy Copy Secure (provisioned with Drive Wizard 1.0.81): files use three-key Triple-DES in CBC mode, but a fixed 32-byte certificate embedded in the Mac and Windows viewers decrypts a configuration file that holds the 24-byte 3DES key, 8-byte IV and a hardcoded password (123456). The Mac viewer compares the password with a plain string comparison, so the password only gates the viewer UI. Anti-capture checks (process enumeration, screenshot and clipboard monitoring, detection of ScreenFlow, Camtasia, Debut, Grab and QuickTime) are bypassable.
The author deliberately skipped coordinated disclosure, arguing that issued devices cannot be recalled or updated. The sources report no CVE assignments, CVSS scores, vendor responses or exploitation in the wild; severity is an analyst estimate. Defender takeaway: password prompts and copy restrictions in these products do not provide cryptographic confidentiality, and AI-assisted static analysis lowers the cost of finding such flaws in other legacy encryption tools. Note: the hunt skeleton and GBHackers attribute the work to OpenAI Codex, while the primary post refers only to 'Codex' and 'the AI' without naming a model.
MITRE ATT&CK techniques used in TL-2026-4434
Collection
T1005 Data from Local System; T1025 Data from Removable Media; T1113 Screen Capture
Initial Access
Defense Evasion
T1078.001 Default Accounts; T1140 Deobfuscate/Decode Files or Information
Credential Access
Affected products and versions in AI-assisted reverse engineering (OpenAI Codex + Binary Ninja
- Netac — NetacFileLock
Vulnerable versions: version not stated in source - SecZure — YutianDun (AQUP)
Vulnerable versions: version not stated in source - KakaSoft — USB Copy Protection
Vulnerable versions: 5.6.0.299 - Nexcopy — Copy Secure (Drive Wizard)
Vulnerable versions: Drive Wizard 1.0.81
Remediation for AI-assisted reverse engineering (OpenAI Codex + Binary Ninja
Patches
- No vendor patches or advisories were reported in the sources
Immediate actions
- Do not rely on NetacFileLock, SecZure YutianDun, KakaSoft USB Copy Protection or Nexcopy Copy Secure password protection for confidentiality of sensitive data
- Inventory issued USB drives and removable media using these products and treat their contents as recoverable by anyone holding the device
- Change any password reused from these products, since NetacFileLock writes passwords to diagnostic logs and several products ship fixed or default passwords
Workarounds
- Re-encrypt sensitive files with a standard tool before placing them on removable media
- Hunt for the vendor tool binaries and artifacts listed in the IOCs to locate affected drives and hosts
Longer-term hardening
- Use vetted full-disk or container encryption (for example BitLocker To Go, LUKS or VeraCrypt) with keys derived from user secrets via a strong KDF
- Enforce removable-media DLP and device-control policy and prefer centrally managed, hardware-encrypted drives
- Include AI-assisted reverse engineering in threat models for legacy or proprietary crypto products
Weaknesses (CWE) in AI-assisted reverse engineering (OpenAI Codex + Binary Ninja
Timeline of AI-assisted reverse engineering (OpenAI Codex + Binary Ninja
- Xusheng Li publishes 'Examining USB Copy Protection' in Paged Out! issue 5 (November 2024), earlier manual research into USB copy-protection software.
- AI analysis of Nexcopy Copy Secure / Drive Wizard 1.0.81 (about 10 minutes, 5 prompts) finds a fixed embedded certificate decrypting a config file with the 3DES key and hardcoded password.
- AI analysis of KakaSoft USB Copy Protection 5.6.0.299 (about 9 minutes) and SecZure YutianDun (built-in Buffer and System accounts, 64-bit key entropy) yields passwordless decryption paths.
- AI agent with Binary Ninja MCP reproduces the 2025 NetacFileLock findings (fixed AES-256 key, ECB-style encryption, MD5 checks) in about 7 minutes using static analysis.
- Binary Ninja blog post 'Breaking more encrypted USB drives with AI' is published, bypassing coordinated disclosure because issued devices cannot be recalled or updated.
- GBHackers reports the research; no CVEs, CVSS scores, vendor responses or in-the-wild exploitation are cited.
Sources cited for AI-assisted reverse engineering (OpenAI Codex + Binary Ninja
- Breaking more encrypted USB drives with AI (Binary Ninja blog, Xusheng Li)
- OpenAI Codex Breaks USB Drive Encryption in Minutes, Exposing Critical Security Flaws (GBHackers)
- Breaking Encrypted USB Drives with Time-Travel Debugging (slides, xusheng6)
- Examining USB Copy Protection, Paged Out! issue 5
- Xusheng Li (xusheng6) GitHub profile
- Binary Ninja MCP server (fosdickio)
- Binary Ninja
Detection coverage for TL-2026-4434
As of 2026-10-26, Threadlinqs Intelligence publishes 9 detection rule(s) for TL-2026-4434 across Splunk SPL, Microsoft KQL and Sigma, covering 14 indicator(s) of compromise. The whole corpus is readable without an account; a free account unlocks full detection query text in Splunk SPL, Microsoft KQL and Sigma; paid tiers add raw indicator values, correlation and the MCP server. Threadlinqs MCP server · View plans.