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.

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.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

The remote Fedora 42 host has a package installed that is affected by multiple vulnerabilities as referenced in the FEDORA-2026-f04da48123 advisory.

    update to xen 4.19.5

    ----

    Use after free of paging structures in EPT [XSA-480, CVE-2026-23554]     Xenstored DoS by unprivileged domain [XSA-481, CVE-2026-23555]


Tenable has extracted the preceding description block directly from the Fedora security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The remote Fedora 44 host has a package installed that is affected by multiple vulnerabilities as referenced in the FEDORA-2026-f884fd0313 advisory.

    update to xen 4.21.1

    ----

    Use after free of paging structures in EPT [XSA-480, CVE-2026-23554]     Xenstored DoS by unprivileged domain [XSA-481, CVE-2026-23555]


Tenable has extracted the preceding description block directly from the Fedora security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The remote SUSE Linux SLED15 / SLED_SAP15 / SLES15 / SLES_SAP15 host has packages installed that are affected by multiple vulnerabilities as referenced in the SUSE-SU-2026:1093-1 advisory.

    - CVE-2026-23554: xen: Use after free of paging structures in EPT (bsc#1259247, XSA-480)
    - CVE-2026-23555: xen: Xenstored DoS by unprivileged domain (bsc#1259248, XSA-481)

Tenable has extracted the preceding description block directly from the SUSE security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The remote Fedora 43 host has a package installed that is affected by multiple vulnerabilities as referenced in the FEDORA-2026-8ae1a1c3d7 advisory.

    Use after free of paging structures in EPT [XSA-480, CVE-2026-23554]     Xenstored DoS by unprivileged domain [XSA-481, CVE-2026-23555]

Tenable has extracted the preceding description block directly from the Fedora security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The remote SUSE Linux SLES15 / SLES_SAP15 / openSUSE 15 host has packages installed that are affected by multiple vulnerabilities as referenced in the SUSE-SU-2026:0908-1 advisory.

    - CVE-2026-23554: xen: Use after free of paging structures in EPT (bsc#1259247, XSA-480)
    - CVE-2026-23555: xen: Xenstored DoS by unprivileged domain (bsc#1259248, XSA-481)

Tenable has extracted the preceding description block directly from the SUSE security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - 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. (CVE-2026-23555)

Note that Nessus relies on the presence of the package as reported by the vendor.

ID	Name	Product	Family	Severity
318808	Xen: Xenstored DoS by unprivileged domain (XSA-481)	Nessus	Misc.	high
304454	Fedora 42 : xen (2026-f04da48123)	Nessus	Fedora Local Security Checks	high
304345	Fedora 44 : xen (2026-f884fd0313)	Nessus	Fedora Local Security Checks	high
304123	SUSE SLED15 / SLES15 Security Update : xen (SUSE-SU-2026:1093-1)	Nessus	SuSE Local Security Checks	high
303312	Fedora 43 : xen (2026-8ae1a1c3d7)	Nessus	Fedora Local Security Checks	high
302848	SUSE SLES15 / openSUSE 15 Security Update : xen (SUSE-SU-2026:0908-1)	Nessus	SuSE Local Security Checks	high
302813	Linux Distros Unpatched Vulnerability : CVE-2026-23555	Nessus	Misc.	high

Detections

Analytics

CVE-2026-23555

high

Tenable Plugins

high

high

high

high

high

high

high