Buffer overflow in Linux kernel and Fedora - CVE-2020-9391
Published: February 25, 2020 / Updated: August 8, 2020
Vulnerability identifier: #VU34808
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2020-9391
CWE-ID: CWE-119
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vendor: Linux Foundation
Fedoraproject
Fedoraproject
Affected software:
Linux kernel
Fedora
Linux kernel
Fedora
Detailed vulnerability description
The vulnerability allows a local authenticated user to perform a denial of service (DoS) attack.
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.
How to mitigate CVE-2020-9391
Install update from vendor's website.
Sources
- http://www.openwall.com/lists/oss-security/2020/02/25/6
- https://bugzilla.redhat.com/show_bug.cgi?id=1797052
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=dcde237319e626d1ec3c9d8b7613032f0fd4663a
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/O4LH35HOPBJIKYHYFXMBBM75DN75PZHZ/
- https://security.netapp.com/advisory/ntap-20200313-0003/