CVE-2026-23555 Affecting xen package, versions <4.18.5-r5


Severity

Recommended
0.0
high
0
10

Snyk's Security Team recommends NVD's CVSS assessment. Learn more

Threat Intelligence

EPSS
0.18% (8th percentile)

Do your applications use this vulnerable package?

In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.

Test your applications
  • Snyk IDSNYK-ALPINE320-XEN-15689563
  • published19 Mar 2026
  • disclosed23 Mar 2026

Introduced: 19 Mar 2026

CVE-2026-23555  (opens in a new tab)

How to fix?

Upgrade Alpine:3.20 xen to version 4.18.5-r5 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream xen package and not the xen package as distributed by Alpine. See How to fix? for Alpine:3.20 relevant fixed versions and status.

Any guest issuing a Xenstore command accessing a node using the (illegal) node path "/local/domain/", will crash xenstored due to a clobbered error indicator in xenstored when verifying the node path.

Note that the crash is forced via a failing assert() statement in xenstored. In case xenstored is being built with NDEBUG #defined, an unprivileged guest trying to access the node path "/local/domain/" will result in it no longer being serviced by xenstored, other guests (including dom0) will still be serviced, but xenstored will use up all cpu time it can get.

CVSS Base Scores

version 3.1