What’s Vulnerable › Vulnerabilities

CVE-2020-9391

• Severity: medium (CVSS 5.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.5% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2020-02-25 · updated 2026-06-17
• Weakness: CWE-787

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.

Affected products

• Fedoraproject Fedora: 31
• Linux kernel: from 5.5 through 5.5.6; 5.4
• Active IQ Unified Manager for VMware vSphere, Linux, and Microsoft Windows: all versions
• NetApp Cloud Backup: all versions
• NetApp Data Availability Services: all versions
• NetApp H410C Firmware: all versions
• NetApp Hci Management Node: all versions
• NetApp Solidfire: all versions
• NetApp Steelstore Cloud Integrated Storage: all versions

References

• 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%40lists.fedoraproject.org/message/O4LH35HOPBJIKYHYFXMBBM75DN75PZHZ/
• https://security.netapp.com/advisory/ntap-20200313-0003/
• 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%40lists.fedoraproject.org/message/O4LH35HOPBJIKYHYFXMBBM75DN75PZHZ/
• https://security.netapp.com/advisory/ntap-20200313-0003/

Get alerted when CVE-2020-9391 or the next vulnerability affects your stack