Medium severity · published Feb 25, 2020
CVE-2020-9391
An issue was discovered in the Linux kernel 5.4 and 5.5 through 5.5.6 on the AArch64 architecture
5.5
CVSS
0.5%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 44% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
KE
Kernel · Linux
5.5 through 5.5.6; 5.4 · source: NVD
AI
Active IQ Unified Manager · Netapp
All versions, or not specified · source: NVD
CB
Cloud Backup · Netapp
All versions, or not specified · source: NVD
DA
Data Availability Services · Netapp
All versions, or not specified · source: NVD
FE
Fedora · Fedoraproject
31 · source: NVD
HF
H410c Firmware · Netapp
All versions, or not specified · source: NVD
HM
Hci Management Node · Netapp
All versions, or not specified · source: NVD
SO
Solidfire · Netapp
All versions, or not specified · source: NVD
SC
Steelstore Cloud Integrated Storage · Netapp
All versions, or not specified · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2020-9391
CVE.org
https://www.cve.org/CVERecord?id=CVE-2020-9391
Exploit
http://www.openwall.com/lists/oss-security/2020/02/25/6
Exploit
https://bugzilla.redhat.com/show_bug.cgi?id=1797052
Mailing List
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=dcde237319e626d1ec3c9d8b7613032f0fd4663a
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/O4LH35HOPBJIKYHYFXMBBM75DN75PZHZ/
Third Party Advisory
https://security.netapp.com/advisory/ntap-20200313-0003/
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