Prominent Windows PC makers, including Acer, Hewlett-Packard and Lenovo, have made "egregious" omissions in the software updaters they bundle with notebooks that leave customers at risk from attack by cyber-criminals, a security firm contended.

"It's 2016," said Steve Manzuik, director of security research at Duo Security, in an interview. "[These updaters show] a lack of basic security measures that you should use."

Earlier this week, Duo published a report detailing an examination of 10 Windows laptops from five OEMs (original equipment manufacturers) -- Acer, Asus, Dell, HP and Lenovo -- that focused on the software updating tools the vendors pre-loaded on their machines.

Those updaters are used to keep the proprietary and third-party software bundled with new PCs up to date. OEMs rely on the updaters to refresh device drivers and their own support tools, as well as the in-house and third-party applications pre-installed on new systems. The latter is known by a slew of derisive labels, including "bloatware" and "crapware," because they're often low-value applications that OEMs are paid to pack on the drive.

Updaters come with a big bulls-eye painted on their backs, said Duo. "Any software that downloads and executes arbitrary binaries is an enticing target to attackers," the firm wrote in its report. "Targeting the transmission of executable files on the wire is a no-brainer."

By definition, updaters download binary files, then execute them. If criminals intercepted an updater's traffic between PC and server -- most likely in a classic "man-in-the-middle" attack performed, say, over an unsecured Wi-Fi network like those at coffee shops and airports -- they could twist the code to have the updater install and run malware.

That's why top-tier software updaters, like those operated by Microsoft and Apple, aggressively secure the process. The most important components of that lock-down, said Duo: Encrypting the device-to-server-and-back traffic using the TLS (transport layer security) protocol, the successor to SSL (secure sockets layer); and digitally signing every update's "manifest," or list of files, so that it can't be changed.

Too bad no one told the OEM updaters' programmers that.

Of the five vendors, only Dell and Lenovo transmitted the update manifest over an encrypted channel using TLS; the rest exposed the list of new packages and software update to interception by hackers. And of the five, only Lenovo -- and then only on one of the two updaters it uses -- digitally signed the manifest to protect it from unauthorized modification. (Confusingly, Lenovo and Dell used different updaters on different notebooks in their line, more evidence of sloppy work.)

"It's a combination of these two things," said Manzuik, referring to encryption and signing being omitted.

But the lack of manifest signing was the key, according to Darren Kemp, a Duo security researcher. "The manifest drives the updates," Kemp said. "[Only one] was signed at all. If the OEMs had implemented this properly, it would have stopped almost every attack. 'Egregious' really is the word to describe [the OEMs' failures.]"

Duo found security flaws in every one of the updaters it looked at, and with the lack of encryption and manifest signing, judged exploiting those vulnerabilities as trivial, or in the words the company used in a supporting blog post written by Kemp, "The level of sophistication required to exploit most of the vulnerabilities we found is somewhere between that possessed by a coffee stain on the Duo lunch room floor and your average potted plant."

Manzuik's and Kemp's best advice for buyers of new crapware-infested PCs was to immediately wipe the device's drive and re-install a clean copy of Windows. While that is standard practice for enterprises -- which install a company-approved image -- many consumers and smaller businesses find that difficult. In lieu of a clean install, Duo recommended that users uninstall the unwanted software, including the updaters.

Microsoft touts its Signature line of PCs -- OEM notebooks and desktops that have no or little bloatware -- as a way to circumvent the problem. But of the three Signature-branded notebooks examined, one each from Asus, Dell and HP, Duo found that all still included the flawed updaters.