CVE-2026-45644

Status: AnalyzedHigh (8)—

Improper neutralization of input during web page generation ('cross-site scripting') in Microsoft Live Share Canvas SDK allows an authorized attacker to elevate privileges over a network.

CVSS

Version: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H
Base score: 8

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 0.81%
Percentile among all scored CVEs: 55
Score date: 10/5/2026

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

🎯 ATT&CK techniques

How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.

ExploitationT1189 Drive-by Compromiseinitial access95 %
Primary impactT1059.007 JavaScriptexecution85 %
Secondary impactT1068 Exploitation for Privilege Escalationprivilege escalation75 %

XSS (CWE-79) en aplicación web con UI:R y PR:L; ejecución de JavaScript en navegador (T1059.007) y escalada de privilegios confirmada por "elevate privileges" en descripción.

Inferred by our analysis agent from the official description, CVSS vector and CWE, and checked by a supervisor. May contain errors.

🛡️ ATT&CK mitigations that cover these techniques

Restrict Web-Based Content Execution Prevention Application Isolation and Sandboxing Exploit Protection Update Software User Training

Affected technologies (1)

Microsoft — Live Share Canvas

CWEs

CWE-79

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-45644

Raw JSON (NVD)

Show

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  "lastModified": "2026-07-23T08:10:00.137",
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