Medium severity · published Feb 10, 2026
CVE-2026-21529
Azure HDInsight Spoofing Vulnerability
5.4
CVSS
0.7%
EPSS
No
On KEV
Description
Improper neutralization of input during web page generation ('cross-site scripting') in Azure HDInsights allows an authorized attacker to perform spoofing over a network.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
Required
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.7% · higher than 52% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
AH
Azure HDInsight · Microsoft
1.0 before 5.1 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-21529
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-21529
Vendor Advisory
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21529
More from Azure HDInsight
9.8
CVE-2023-36419
Azure HDInsight Apache Oozie Workflow Scheduler XXE Elevation of Privilege Vulnerability
7.5
CVE-2026-85891
Azure HDInsight Information Disclosure Vulnerability
7.2
CVE-2026-81349
Azure HDInsight Ambari Elevation of Privilege Vulnerability
7.2
CVE-2023-38156
Azure HDInsight Apache Ambari JDBC Injection Elevation of Privilege Vulnerability
4.6
CVE-2023-35394
Azure HDInsight Jupyter Notebook Spoofing Vulnerability