ISOMAN

CVE

CVE-2019-19922

kernel/sched/fair.c in the Linux kernel before 5.3.9, when cpu.cfs_quota_us is used (e.g., with Kubernetes), allows attackers to cause a denial of service against non-cpu-bound applications by generating a workload that triggers unwanted slice expiration, aka CID-de53fd7aedb1. (In other words, although this slice expiration would typically be seen with benign workloads, it is possible that an attacker could calculate how many stray requests are required to force an entire Kubernetes cluster into a low-performance state caused by slice expiration, and ensure that a DDoS attack sent that number of stray requests. An attack does not affect the stability of the kernel; it only causes mismanagement of application execution.)

Severity
MEDIUM
CVSS
5.5
Published
Modified

Linked Releases

DistributionReleaseStatusEvidence
Ubuntu18.04.6 amd64 desktopunknownsource
Ubuntu18.04.6 amd64 live-serverunknownsource

References

  1. https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.3.9
  2. https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=de53fd7aedb100f03e5d2231cfce0e4993282425
  3. https://github.com/kubernetes/kubernetes/issues/67577
  4. https://github.com/torvalds/linux/commit/de53fd7aedb100f03e5d2231cfce0e4993282425
  5. https://lists.debian.org/debian-lts-announce/2020/01/msg00013.html
  6. https://relistan.com/the-kernel-may-be-slowing-down-your-app
  7. https://security.netapp.com/advisory/ntap-20200204-0002/
  8. https://usn.ubuntu.com/4226-1/
  9. https://www.oracle.com/security-alerts/cpuApr2021.html
  10. https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.3.9
  11. https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=de53fd7aedb100f03e5d2231cfce0e4993282425
  12. https://github.com/kubernetes/kubernetes/issues/67577
  13. https://github.com/torvalds/linux/commit/de53fd7aedb100f03e5d2231cfce0e4993282425
  14. https://lists.debian.org/debian-lts-announce/2020/01/msg00013.html
  15. https://relistan.com/the-kernel-may-be-slowing-down-your-app
  16. https://security.netapp.com/advisory/ntap-20200204-0002/
  17. https://usn.ubuntu.com/4226-1/
  18. https://www.oracle.com/security-alerts/cpuApr2021.html