CVE-2020-9391

Public Exploit

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.

Category

5.5
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.16%
Vendor Advisory fedoraproject.org Vendor Advisory kernel.org
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=dcde237319e626d1ec3c9d8b7613032f0fd4663a patch vendor advisory mailing list
https://bugzilla.redhat.com/show_bug.cgi?id=1797052 patch exploit third party advisory issue tracking
http://www.openwall.com/lists/oss-security/2020/02/25/6 mailing list third party advisory exploit
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/O4LH35HOPBJIKYHYFXMBBM75DN75PZHZ/ vendor advisory
https://security.netapp.com/advisory/ntap-20200313-0003/ third party advisory

Frequently Asked Questions

What is the severity of CVE-2020-9391?
CVE-2020-9391 has been scored as a medium severity vulnerability.
How to fix CVE-2020-9391?
To fix CVE-2020-9391, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2020-9391 being actively exploited in the wild?
It is possible that CVE-2020-9391 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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