Vulnerability in Xen
CVE-2022-26363
x86 pv: Insufficient care with non-coherent mappings T[his CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] Xen maintains a type reference count for pages, in addition to a regular reference count. This scheme is used to maintain invariants required for Xen's safety, e.g. PV guests may not have direct writeable access to pagetables; updates need auditing by Xen. Unfortunately, Xen's safety logic doesn't account for CPU-induced cache non-coherency; cases where the CPU can cause the content of the cache to be different to the content in main memory. In such cases, Xen's safety logic can incorrectly conclude that the contents of a page is safe.
EPSS: 0.003 (26.6th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 6.7 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H.
Affected products
- Xen — versions consult Xen advisory XSA-402
- Debian Debian_linux — versions 11.0
- Fedoraproject Fedora — versions 35, 36
References
- security@xen.org (x_refsource_MISC, Vendor Advisory)
- security@xen.org (x_refsource_CONFIRM, Patch, Vendor Advisory)
- security@xen.org (mailing-list, x_refsource_MLIST, Mailing List, Third Party Advisory)
- security@xen.org (x_refsource_FEDORA, vendor-advisory)
- security@xen.org (vendor-advisory, Third Party Advisory, x_refsource_DEBIAN)
- security@xen.org (x_refsource_FEDORA, vendor-advisory)
- security@xen.org (vendor-advisory, Third Party Advisory, x_refsource_GENTOO)
Frequently asked questions
- What is CVE-2022-26363?
- CVE-2022-26363 is a medium-severity vulnerability in Xen. CVSS score: 6.7/10. Published 2022-06-09.
- How severe is CVE-2022-26363?
- Medium severity. CVSS v3 base score is 6.7 out of 10.