USN-4390-1: Linux kernel vulnerabilities

Severity

Medium

Vendor

Canonical Ubuntu

Description

It was discovered that the F2FS file system implementation in the Linux kernel did not properly perform bounds checking on xattrs in some situations. A local attacker could possibly use this to expose sensitive information (kernel memory). (CVE-2020-0067)

It was discovered that memory contents previously stored in microarchitectural special registers after RDRAND, RDSEED, and SGX EGETKEY read operations on Intel client and Xeon E3 processors may be briefly exposed to processes on the same or different processor cores. A local attacker could use this to expose sensitive information. (CVE-2020-0543)

Piotr Krysiuk discovered that race conditions existed in the file system implementation in the Linux kernel. A local attacker could use this to cause a denial of service (system crash). (CVE-2020-12114)

It was discovered that the USB susbsystem’s scatter-gather implementation in the Linux kernel did not properly take data references in some situations, leading to a use-after-free. A physically proximate attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2020-12464)

Xiumei Mu discovered that the IPSec implementation in the Linux kernel did not properly encrypt IPv6 traffic in some situations. An attacker could use this to expose sensitive information. (CVE-2020-1749)

Dmitry Vyukov discovered that the SELinux netlink security hook in the Linux kernel did not validate messages in some situations. A privileged attacker could use this to bypass SELinux netlink restrictions. (CVE-2020-10751)

CVEs contained in this USN include: CVE-2020-0543, CVE-2020-12114, CVE-2020-10751, CVE-2020-12464, CVE-2020-1749, CVE-2020-0067.

Affected Cloud Foundry Products and Versions

Severity is medium unless otherwise noted.

• Xenial Stemcells
  • 170.x versions prior to 170.221
  • 250.x versions prior to 250.200
  • 315.x versions prior to 315.185
  • 456.x versions prior to 456.114
  • 621.x versions prior to 621.76
  • All other stemcells not listed.

Mitigation

Users of affected products are strongly encouraged to follow the mitigations below. The Cloud Foundry project recommends upgrading the following releases:

• Xenial Stemcells
  • Upgrade 170.x versions to 170.221 or greater
  • Upgrade 250.x versions to 250.200 or greater
  • Upgrade 315.x versions to 315.185 or greater
  • Upgrade 456.x versions to 456.114 or greater
  • Upgrade 621.x versions to 621.76 or greater
  • All other stemcells should be upgraded to the latest version available on bosh.io.

History

2020-06-10: Initial vulnerability report published.