CVE-2026-23555
Fixed in a distro release EPSS <1%CVSS 7.1
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.
Products: xen
Distro releases
| Release | Package | Fixed in |
|---|---|---|
| Alpine 3.20 | xen | 4.18.5-r5 |
| Alpine 3.21 | xen | 4.19.4-r2 |
| Alpine 3.22 | xen | 4.20.2-r2 |
| Alpine 3.23 | xen | 4.20.2-r2 |
| Alpine 3.24 | xen | 4.21.0-r3 |
| Debian 13 | xen | 4.20.3+127-gc42374a105-0+deb13u1 |
| Debian 14 | xen | 4.20.3+127-gc42374a105-1 |
| SUSE Linux Enterprise Module for Basesystem 15 SP7 | xen | 4.20.2_08-150700.3.28.1 |
| SUSE Linux Enterprise Module for Server Applications 15 SP7 | xen | 4.20.2_08-150700.3.28.1 |
| SUSE Linux Enterprise Server 15 SP6-LTSS | xen | 4.18.5_12-150600.3.40.1 |
| SUSE Linux Enterprise Server for SAP Applications 15 SP6 | xen | 4.18.5_12-150600.3.40.1 |
| Ubuntu 16.04 LTS | xen | no fix |
| Ubuntu 18.04 LTS | xen | no fix |
| Ubuntu 20.04 LTS | xen | no fix |
| Ubuntu 22.04 LTS | xen | no fix |
| Ubuntu 24.04 LTS | xen | no fix |
| Ubuntu 25.10 | xen | no fix |
| Ubuntu 26.04 LTS | xen | no fix |
| Ubuntu 26.10 | xen | no fix |
| openSUSE Leap 15.6 | xen | 4.18.5_12-150600.3.40.1 |
| openSUSE Tumbleweed | xen | 4.21.1_02-1.1 |