Severity

Medium

Vendor

Canonical Ubuntu

Versions Affected

• Canonical Ubuntu 16.04

Description

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

Affected VMware Products and Versions

Severity is medium unless otherwise noted.

Vulnerable Cloud Foundry components individually listed here.

Impacted stemcells may be updated independently of upgrading Pivotal Application Service or PCF Isolation Segment.

• Isolation Segment
  • 2.6.x versions prior to 2.6.19
  • 2.7.x versions prior to 2.7.14
  • 2.8.x versions prior to 2.8.8
  • 2.9.x versions prior to 2.9.2
• Operations Manager
  • 2.6.x versions prior to 2.6.26
  • 2.7.x versions prior to 2.7.16
  • 2.8.x versions prior to 2.8.7
• VMware Tanzu Application Service for VMs
  • 2.6.x versions prior to 2.6.20
  • 2.7.x versions prior to 2.7.14
  • 2.8.x versions prior to 2.8.8
  • 2.9.x versions prior to 2.9.2

Mitigation

Users of affected products are strongly encouraged to follow the mitigation below. The Cloud Foundry security team recommends upgrading the affected OSS components listed here if applicable. Upgrade Pivotal products that use earlier versions of CF components to new Pivotal releases using new versions linked above. On the Pivotal Network product page for each release, check the Depends On section and/or Release Notes for this information. Releases that have fixed this issue include:

• Isolation Segment
  • 2.6.19
  • 2.7.14
  • 2.8.8
  • 2.9.2
• Operations Manager
  • 2.6.26
  • 2.7.16
  • 2.8.7
• VMware Tanzu Application Service for VMs
  • 2.6.20
  • 2.7.14
  • 2.8.8
  • 2.9.2

References

• https://people.canonical.com/~ubuntu-security/cve/CVE-2020-8428
• https://people.canonical.com/~ubuntu-security/cve/CVE-2020-8834
• https://people.canonical.com/~ubuntu-security/cve/CVE-2020-8992
• https://usn.ubuntu.com/4318-1/
• https://cloudfoundry.org/blog/usn-4318-1

History

2020-04-06: Initial vulnerability report published.