VULNERABILITY INTELLIGENCE

CVE-2021-26933

CVSS score5.5 MEDIUM
EPSS probability0.33%
CISA KEVNot currently listed
Published2021-02-17
Last modified2026-06-17
CVSS vectorCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

Description

An issue was discovered in Xen 4.9 through 4.14.x. On Arm, a guest is allowed to control whether memory accesses are bypassing the cache. This means that Xen needs to ensure that all writes (such as the ones during scrubbing) have reached the memory before handing over the page to a guest. Unfortunately, the operation to clean the cache is happening before checking if the page was scrubbed. Therefore there is no guarantee when all the writes will reach the memory.

Weakness classification

  • nvd@nist.gov: NVD-CWE-noinfo

Primary references