CVE Tools
Sign in

CVE-2026-23557

Xenstored DoS via XS_RESET_WATCHES command

Published: May 19, 2026Updated: May 19, 2026 Sources: CVE List NVDCWE-617
NVD MITRE
6.5CVSSMEDIUM
EPSS Score
0.2%
Top 94.7%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available

Description

Any guest can cause xenstored to crash by issuing a XS_RESET_WATCHES command within a transaction due to an assert() triggering. In case xenstored was built with NDEBUG #defined nothing bad will happen, as assert() is doing nothing in this case. Note that the default is not to define NDEBUG for xenstored builds even in release builds of Xen.

CVSS Vector Breakdown

AV:LAC:LPR:LUI:NS:CC:NI:NA:H
Exploitability
AV:LAttack Vector
Local
AC:LAttack Complexity
Low
PR:LPrivileges Required
Low
UI:NUser Interaction
None
Scope
S:CScope
Changed
Impact
C:NConfidentiality
None
I:NIntegrity
None
A:HAvailability
High
Open in CVSS calculator →

Weaknesses

CWE-617

Affected Products

XenXen
On-prem
Cloud & SaaS / virtualization
xenxen
On-prem
Cloud & SaaS / virtualization
xenoss-projectGBCloud & SaaSaka xapi, qemu

Attack Graph

Products CVE Techniques Tactics

Click technique nodes to view MITRE ATT&CK details. Scroll to zoom, drag to pan.

Exploitability

Official Patch Available
Workaround Available

MITRE ATT&CK

1 technique
Impact
View detailed technique mapping

References

https://xenbits.xenproject.org/xsa/advisory-484.html
xenbits.xenproject.org
http://www.openwall.com/lists/oss-security/2026/04/28/11
openwall.com
http://xenbits.xen.org/xsa/advisory-484.html
xenbits.xen.org

Timeline

Published
May 19, 2026
Last Updated
May 19, 2026

Unlock Complete Vulnerability Intelligence

Get the full picture for CVE-2026-23557 and every CVE in our database. Create a free account — no credit card required.

Create Free Account
Plain-language analysis
Impact assessment and exploitation scenario in plain English
Attack graph visualization
Interactive attack path and kill chain mapping
Exploit details & PoC links
ExploitDB, Metasploit, GitHub PoCs with direct links
Nuclei scanner templates
Ready-to-use vulnerability scanner templates
Full remediation guide
Patch instructions, workarounds, and compliance impact
Interactive AI chat
Ask questions about this vulnerability in natural language
Related vulnerabilities
Semantically similar CVEs and attack patterns
REST API & MCP access
Integrate vulnerability data into your workflows