Vulnerability in Xen

CVE-2019-18422

An issue was discovered in Xen through 4.12.x allowing ARM guest OS users to cause a denial of service or gain privileges by leveraging the erroneous enabling of interrupts. Interrupts are unconditionally unmasked in exception handlers. When an exception occurs on an ARM system which is handled without changing processor level, some interrupts are unconditionally enabled during exception entry. So exceptions which occur when interrupts are masked will effectively unmask the interrupts. A malicious guest might contrive to arrange for critical Xen code to run with interrupts erroneously enabled. This could lead to data corruption, denial of service, or possibly even privilege escalation. However a precise attack technique has not been identified.

EPSS: 0.018 (76.5th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

References

  • cve@mitre.org (Patch, x_refsource_MISC, Vendor Advisory)
  • cve@mitre.org (mailing-list, x_refsource_MLIST, Patch, Mailing List, Third Party Advisory)
  • cve@mitre.org (x_refsource_FEDORA, vendor-advisory)
  • cve@mitre.org (x_refsource_FEDORA, vendor-advisory)
  • cve@mitre.org (x_refsource_FEDORA, vendor-advisory)
  • cve@mitre.org (vendor-advisory, Third Party Advisory, x_refsource_DEBIAN)
  • cve@mitre.org (mailing-list, x_refsource_BUGTRAQ, Mailing List, Third Party Advisory)

Frequently asked questions

What is CVE-2019-18422?
CVE-2019-18422 is a high-severity vulnerability in Xen, classified under Incorrect Permission Assignment for Critical Resource. CVSS score: 8.8/10. Published 2019-10-31.
How severe is CVE-2019-18422?
High severity. CVSS v3 base score is 8.8 out of 10.