The security flaw was discovered over the summer by security researchers from SafeBreach Labs.
HP has released updates this month to address the issue.
HP desktop and laptop owners are advised to follow instructions detailed in the HP security advisory and update the HP Touchpoint Analytics client at their earliest convenience.
The HP Touchpoint Analytics app is what users normally call "bloatware," a type of software that comes pre-installed on new devices.
The app's purpose is to collect diagnostics data about hardware performance and send the information back to HP.
As such, the app usually whitelisted and runs with admin rights on HP systems -- to be able to access various details from software drivers and other hardware components.
But in a report shared with ZDNet this week, Peleg Hadar, a security researcher with SafeBreach Labs, said he found a way to hijack the application's normal mode of operation and load malicious DLL files to run rogue code with elevated privileges.
Hadar found what security experts call a local privilege escalation (LPE), a type of vulnerability that's quite common in modern software.
The vulnerability won't allow hackers to take over a system from a remote location, but it will allow local apps or malware to funnel malicious commands through its code and execute those operations with full admin rights.
While most LPE vulnerabilities are low risk, this one's severity is amplified by the app's huge install-base -- being found on hundreds of millions of HP desktops and laptops.
This makes this vulnerability attractive to malware gangs, who will see a real benefit to gain by including it into their future exploit chains.