CVE-2020-9391

Name	CVE-2020-9391
Description	An issue was discovered in the Linux kernel 5.4 and 5.5 through 5.5.6 on the AArch64 architecture. It ignores the top byte in the address passed to the brk system call, potentially moving the memory break downwards when the application expects it to move upwards, aka CID-dcde237319e6. This has been observed to cause heap corruption with the GNU C Library malloc implementation.
Source	CVE (at NVD; CERT, LWN, oss-sec, fulldisc, bugtraq, EDB, Metasploit, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, Mageia, GitHub advisories/code/issues, web search, more)

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
linux (PTS)	buster	4.19.249-2	fixed
	buster (security)	4.19.282-1	fixed
	bullseye	5.10.178-3	fixed
	bullseye (security)	5.10.179-1	fixed
	bookworm, sid	6.1.27-1	fixed

The information below is based on the following data on fixed versions.

Package	Type	Release	Fixed Version
linux	source	jessie	(not affected)
linux	source	stretch	(not affected)
linux	source	buster	(not affected)
linux	source	(unstable)	5.5.13-1

Notes

[buster] - linux <not-affected> (Vulnerable code not present)
[stretch] - linux <not-affected> (Vulnerable code not present)
[jessie] - linux <not-affected> (Vulnerable code not present)
https://git.kernel.org/linus/dcde237319e626d1ec3c9d8b7613032f0fd4663a