Dan Goodin over at Ars Technica is reporting about an OpenWRT vulnerability in its package manager, opkg.
From the article:
For almost three years, OpenWRT—the open source operating system that powers home routers and other types of embedded systems—has been vulnerable to remote code-execution attacks because updates were delivered over an unencrypted channel and digital signature verifications are easy to bypass, a researcher said.
[...] Security researcher Guido Vranken, however, recently found that updates and installation files were delivered over unencrypted HTTPs[sic] connections, which are open to attacks that allow adversaries to completely replace legitimate updates with malicious ones. The researcher also found that it was trivial for attackers with moderate experience to bypass digital-signature checks that verify a downloaded update as the legitimate one offered by OpenWTR maintainers. The combination of those two lapses makes it possible to send a malicious update that vulnerable devices will automatically install.
[...] These code-execution exploits are limited in their scope because adversaries must either be in a position to conduct a man-in-the-middle attack or tamper with the DNS server that a device uses to find the update on the Internet.
[...] Exploiting these weaknesses, Vranken was able to create a server that impersonated downloads.openwrt.org and served a malicious update. As long as the malicious file is the same size at the legitimate file, it will be executed by a vulnerable device.
Vranken backs up his claims in a blog post where he provides a proof-of-concept exploit against OpenWRT devices.
The checksum bypass vulnerability in OpenWRT's opkg has been assigned CVE-2020-7982.
Affected versions:
18.06.0-18.06.6
19.07.0
LEDE 17.01.0-17.01.7.
Original blog post with discussion and exploit code
OpenWRT Advisory for this vulnerability
OpenWRT is a Linux distro focused on embedded devices, supports a a variety of SoCs, and is widely used on home routers.
(Score: 2) by exaeta on Wednesday April 01 2020, @07:44PM (6 children)
The Government is a Bird
(Score: 2) by pvanhoof on Wednesday April 01 2020, @07:53PM (2 children)
OpenWRT should stop trying to make their own package manager, and simply adopt dpkg. The reasons behind ipkg and later opkg were trying to safe a few megabytes of memory.
Those reasons are irrelevant nowadays.
Whatever the extremist think of it: each and every router nowadays has at least a few hundred megabytes of RAM. If not gigabytes.
(Score: 2) by exaeta on Wednesday April 01 2020, @08:47PM
The Government is a Bird
(Score: 1, Informative) by Anonymous Coward on Thursday April 02 2020, @12:44AM
"each and every router nowadays has at least a few hundred megabytes of RAM. If not gigabytes"
Not true, and flash is the more limited resource.
(Score: 2) by rigrig on Wednesday April 01 2020, @08:46PM (1 child)
Yes, even here they only fixed the checksum parser and not the validation: once the parser breaks again it will still happily install packages for which no checksum was found.
No one remembers the singer.
(Score: 2) by exaeta on Thursday April 02 2020, @02:49PM
The Government is a Bird
(Score: 0) by Anonymous Coward on Wednesday April 01 2020, @09:57PM
Here is someone performing the exploit live and pwning some n00bs: https://www.youtube.com/watch?v=dQw4w9WgXcQ [youtube.com]
(Score: 1, Informative) by Anonymous Coward on Wednesday April 01 2020, @08:22PM
(Score: 3, Insightful) by RamiK on Wednesday April 01 2020, @08:42PM (3 children)
Seeing how Openwrt is running on your router, that only leaves infrastructure level man-in-the-middle a.k.a. state actors a.k.a. the $5 wrench [xkcd.com] guys.
compiling...
(Score: 0) by Anonymous Coward on Wednesday April 01 2020, @10:47PM (2 children)
Automating the exploitation of devices drives down the cost of extracting information far below $5. So why wouldn't they?
(Score: 0) by Anonymous Coward on Wednesday April 01 2020, @11:00PM (1 child)
If you reuse the wrench, you'll save billions!
(Score: 3, Funny) by petecox on Wednesday April 01 2020, @11:07PM
Just tell the fascist goons you have the virus and they won't come within 2 metres.
And if you can't get out of the way of a flying wrench, you're obviously not Dodgeball material.