CVE-2026-23555
Xenstored DoS by unprivileged domain
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.
INFO
Published Date :
March 23, 2026, 7:16 a.m.
Last Modified :
April 10, 2026, 8:38 p.m.
Remotely Exploit :
No
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | HIGH | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | ||||
| CVSS 3.1 | HIGH | [email protected] |
Solution
- Update Xenstore to the latest stable version.
- Ensure Xenstore is built without NDEBUG defined.
- Apply vendor-provided patches promptly.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-23555.
| URL | Resource |
|---|---|
| https://xenbits.xenproject.org/xsa/advisory-481.html | Patch Vendor Advisory |
| http://www.openwall.com/lists/oss-security/2026/03/17/7 | Mailing List Patch Third Party Advisory |
| http://xenbits.xen.org/xsa/advisory-481.html | Patch Vendor Advisory |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-23555 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-23555
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-23555 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-23555 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
Initial Analysis by [email protected]
Apr. 10, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:L/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H Added CPE Configuration OR *cpe:2.3:o:xen:xen:*:*:*:*:*:*:x86:* versions from (including) 4.18.0 Added Reference Type Xen Project: https://xenbits.xenproject.org/xsa/advisory-481.html Types: Patch, Vendor Advisory Added Reference Type CVE: http://www.openwall.com/lists/oss-security/2026/03/17/7 Types: Mailing List, Patch, Third Party Advisory Added Reference Type CVE: http://xenbits.xen.org/xsa/advisory-481.html Types: Patch, Vendor Advisory -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Mar. 23, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:L/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H Added CWE CWE-617 -
CVE Modified by af854a3a-2127-422b-91ae-364da2661108
Mar. 23, 2026
Action Type Old Value New Value Added Reference http://www.openwall.com/lists/oss-security/2026/03/17/7 Added Reference http://xenbits.xen.org/xsa/advisory-481.html -
New CVE Received by [email protected]
Mar. 23, 2026
Action Type Old Value New Value Added 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. Added Reference https://xenbits.xenproject.org/xsa/advisory-481.html