Azure HDInsight Spoofing Vulnerability

published 2026-02-10 8 mo ago modified 2026-08-19 2 mo ago also EUVD-2026-7335

cvss: 5.7; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.7%; EPSS 0.7% chance of exploitation in 30 days, percentile 51%
public exploits: 0; none known

Improper neutralization of input during web page generation ('cross-site scripting') in Azure HDInsights allows an authorized attacker to perform spoofing over a network.

Patch / fix

fixed in 1 links 1

Microsoft Azure HDInsight 5.1

msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21529 advisory

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: 8 mo ago (2026-02-11)

Exploit prediction

0.65% chance of exploitation in the next 30 days, higher than 51% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	5.7	CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C
CNA	3.1	5.7	CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:H
NVD	3.1	5.4	CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

Affected products

Microsoft Azure HDInsight

Classification

Weakness

CWE-79 Improper Neutralization of Input During Web Page Generation

References

msrc.microsoft.com /update-guide/vulnerability/CVE-2026-21529
vendor-advisory, patch

Sources

CVE List CVE-2026-21529
NVD CVE-2026-21529

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary