Medium
Canonical Ubuntu
Al Viro discovered that the vfs layer in the Linux kernel contained a use- after-free vulnerability. A local attacker could use this to cause a denial of service (system crash) or possibly expose sensitive information (kernel memory). (CVE-2020-8428)
Gustavo Romero and Paul Mackerras discovered that the KVM implementation in the Linux kernel for PowerPC processors did not properly keep guest state separate from host state. A local attacker in a KVM guest could use this to cause a denial of service (host system crash). (CVE-2020-8834)
Shijie Luo discovered that the ext4 file system implementation in the Linux kernel did not properly check for a too-large journal size. An attacker could use this to construct a malicious ext4 image that, when mounted, could cause a denial of service (soft lockup). (CVE-2020-8992)
CVEs contained in this USN include: CVE-2020-8428, CVE-2020-8834, CVE-2020-8992.
Severity is medium unless otherwise noted.
Users of affected products are strongly encouraged to follow the mitigations below. The Cloud Foundry project recommends upgrading the following releases:
2020-04-06: Initial vulnerability report published.