SF-LABS-2026-02 / BLANK CHECK / Vulnerability Disclosure
Intuit QuickBooks Desktop BLANK CHECK Local Privilege Escalation
A standard, non-administrator user can gain full SYSTEM control of any Windows machine running QuickBooks Desktop, with no admin rights, no reboot and no user interaction. Confirmed on the current, fully-updated release. Reported to Intuit. Full details and proof-of-concept follow once the disclosure window closes.
Demonstration
Proof-of-Concept Video
Video proof-of-concept will be added when available. The recording shows the escalation path end-to-end, from the unprivileged-user starting state to the SYSTEM shell that results.
Disclosure Record
Timeline and Affected Surface
Public Summary
What is Publicly Disclosed Now
SF-LABS-2026-02 BLANK CHECK is a local privilege escalation in Intuit QuickBooks Desktop confirmed on the current 2024 line with all updates applied. The exploit requires the attacker to already have code execution in a standard non-administrator user context on the target machine. That foothold is the routine outcome of phishing, drive-by download or commodity malware. BLANK CHECK converts any such standard-user foothold into SYSTEM on a fully patched endpoint running affected QuickBooks Desktop versions.
Defensive recommendations for the embargo period are limited to standard local-attack-surface hardening: enforce least-privilege user accounts, restrict execution of unsigned or untrusted binaries from user-writable locations and review installed-software inventory against the public affected-versions list once it lands.
Sherlock Forensics will publish full technical detail when the disclosure window closes or earlier on vendor approval. Researchers and incident response teams who need pre-release notification under NDA can reach the lab at labs@sherlockforensics.com.
About
About Sherlock Forensics Labs
Sherlock Forensics Labs is the research arm of Sherlock Forensics, a Vancouver BC based digital forensics and cybersecurity practice. Lead researcher Ryan Purita is a Principal Security Consultant with 20 years of courtroom-tested digital forensics work plus CISSP, ISSAP and ISSMP certification. The lab follows industry-standard 90-day coordinated disclosure with vendor-acknowledged early-release provisions. See the Labs hub for active and archived disclosures.