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Linux is a family of open source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991 by Linus Torvalds. Linux is typically packaged in a Linux distribution (or distro for short).

Distributions include the Linux kernel and supporting system software and libraries, many of which are provided by the GNU Project. Many Linux distributions use the word "Linux" in their name, but the Free Software Foundation uses the name GNU/Linux to emphasize the importance of GNU software, causing some controversy.

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How exactly "secure" is a container with all capabilities dropped, distroless, with a custom rootfs directory, a static, single binary with chmod set at 100 and file ownership pointed to non-root u... (self.linux)

submitted 1 year ago by GustavoM to c/[email protected]

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ser*, and said non-root user being "nonexistant" (i.e set via ENV)? Can such container -STILL- be exploited/breached through malicious means? Forgot to mention that its a DOCKER container @ title, but there you have it. Just curious.

Thanks in advance.

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[–] ABasilPlant 19 points 1 year ago (1 children)

Absolutely. Check out side channel attacks. The problem here isn't about software exploits, but hardware issues. https://en.wikipedia.org/wiki/Side-channel_attack

Some things to get you started: Meltdown and Spectre: https://en.wikipedia.org/wiki/Meltdown_(security_vulnerability), https://en.wikipedia.org/wiki/Spectre_(security_vulnerability)

Rowhammer: https://en.wikipedia.org/wiki/Row_hammer

These are exploited by malicious processes doing something to the hardware which may result in information about your process(es) being leaked. Now, if this is on your computer, then the chances of encountering a malicious process that exploits this hardware bug would be low.

However, when you move this scenario to the cloud, things become more possible. Your vm/container is being scheduled on CPUs that may/may not be shared by other containers. All it would take is for a malicious guest VM to be scheduled on the same core/CPU as you and try exploiting the same hardware you're sharing.

[–] GustavoM 6 points 1 year ago

Fair enough. Thank you for your input.

[–] mvirts 8 points 1 year ago

There may be unknown container escape vulnerabilities like these https://www.container-security.site/attackers/container_breakout_vulnerabilities.html that can work from an unprivileged container.