High severity · published Mar 23, 2026
CVE-2026-23555
Xenstored DoS by unprivileged domain
7.1
CVSS
0.2%
EPSS
No
On KEV
Description
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 vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
Attack vector
Local
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 8% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
XE
Xen · Xen
4.18.0 and later · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-23555
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-23555
Patch
https://xenbits.xenproject.org/xsa/advisory-481.html
Mailing List
http://www.openwall.com/lists/oss-security/2026/03/17/7
Patch
http://xenbits.xen.org/xsa/advisory-481.html
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