Linux

48709 readers

1442 users here now

From Wikipedia, the free encyclopedia

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.

Rules

Posts must be relevant to operating systems running the Linux kernel. GNU/Linux or otherwise.
No misinformation
No NSFW content
No hate speech, bigotry, etc

Related Communities

Community icon by Alpár-Etele Méder, licensed under CC BY 3.0

founded 5 years ago

MODERATORS

[email protected]

346

Root access vulnerability in glibc library impacts many Linux distros (securityaffairs.com)

submitted 11 months ago by [email protected] to c/[email protected]

88 comments fedilink hide all child comments

you are viewing a single comment's thread
view the rest of the comments

[–] [email protected] 94 points 11 months ago (3 children)

"A qsort vulnerability is due to a missing bounds check and can lead to memory corruption. It has been present in all versions of glibc since 1992. "

This one amazes me. Imagine how many vulnerabilities future researchers will discover in ancient software that persisted/persist for decades.

[–] [email protected] 66 points 11 months ago* (last edited 11 months ago) (2 children)

That's not the main part of the article, just a footnote, for anyone wondering.

The flaw resides in the glibc’s syslog function, an attacker can exploit the flaw to gain root access through a privilege escalation.

The vulnerability was introduced in glibc 2.37 in August 2022.

[–] [email protected] 9 points 11 months ago (2 children)

So, it must be with the BSDs too?

[–] [email protected] 1 points 11 months ago

BSDs use libc

[–] [email protected] 1 points 11 months ago (1 children)

Iirc bad does not use glibc, but I'm not very involved with BSD.

[–] [email protected] 4 points 11 months ago

It wouldn't make sense. Glibc is LGPL licensed, not really compatible with the BSD license...

[–] [email protected] -2 points 11 months ago (2 children)

Wait, why has a compiler system log functionlity?

[–] [email protected] 22 points 11 months ago

glibc is a library, gcc is the compiler.

[–] [email protected] 5 points 11 months ago

You are probably confusing the glibc with gcc and g++. Glibc is an implementation of the C standard library, made by GNU (thats where the g in the name comes from).

If you were to look into it, it uses the syscalls to tell the underlying computer system what to do when you call functions, such as printf.

If you want to read more, see here

[–] xlash123 34 points 11 months ago

C is just crazy. You accidentally forget to put the bounds in a sorting function, and now you are root.

[–] kaputt 7 points 11 months ago (1 children)

According to the link in the article, the qsort() bug can only be triggered with a non-transitive cmp() function. Would such a cmp function ever be useful?

[–] [email protected] 4 points 11 months ago

You don't necessarily have to write a non-transitive cmp() function willingly, it may happen that you write one without realizing due to some edge cases where it's not transitive.