CVE intelligence and bounded remediation

CVE-2020-27672 — Xen Xen security vulnerability

High CVSS 7

An issue was discovered in Xen through 4.14.x allowing x86 guest OS users to cause a host OS denial of service, achieve data corruption, or possibly gain privileges by exploiting a race condition that leads to a use-after-free involving 2MiB and 1GiB superpages.

Severity
High
CVSS
7 (3.1)
Published
2020-10-22
CISA KEV
Not currently listed
Ecosystem
operating-system
Weaknesses
CWE-362, CWE-416

Affected products

  • xen / xen
  • fedoraproject / fedora / 31
  • opensuse / leap / 15.1
  • opensuse / leap / 15.2
  • debian / debian_linux / 10.0

Matched remediation archetype

Use-after-free, double free, and expired resource use

This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.

Check exposure

  • Trace ownership, references, callbacks, asynchronous tasks, and teardown paths around the affected object or resource.
  • Identify reachable inputs and timing or state transitions that can release the object while references remain.
  • Confirm affected builds, allocators, feature flags, architectures, and process privileges.

Remediate safely

  • Apply the maintained ownership or lifetime fix and rebuild all artifacts containing the affected native code.
  • Use explicit ownership, safe reference management, cancellation and join semantics, and idempotent teardown.
  • Add deterministic lifetime tests plus isolated sanitizer and concurrency coverage for shutdown and error paths.

Authoritative sources

Complete CVE record and remediation plan

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