CVE-2026-33521 — HIGH (7.5)

Vulnerability Description

There is s denial of service vulnerability in Esri ArcGIS Server versions 12.0 and prior that may allow a remote, unauthenticated attacker to supply crafted requests that may, under exceptional circumstances, consume all available worker threads and deny service to users. A patch is provided for ArcGIS Server software in General Availability and Extended support status, which includes versions 12.0, 11.5, 11.3, and 11.1. Other versions are in mature or retired status, which are not patch eligible. Users working with unlisted versions are advised to upgrade and apply the patch.

CVSS Score

7.5

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Attack Vector

NETWORK

Attack Complexity

LOW

Privileges Required

NONE

User Interaction

NONE

Scope

UNCHANGED

Confidentiality

NONE

Integrity

NONE

Availability

HIGH

Related Weaknesses (CWE)

CWE-400

References

https://www.esri.com/arcgis-blog/products/trust-arcgis/administration/october-20

FAQ

What is CVE-2026-33521?

CVE-2026-33521 is a vulnerability with a CVSS score of 7.5 (HIGH). There is s denial of service vulnerability in Esri ArcGIS Server versions 12.0 and prior that may allow a remote, unauthenticated attacker to supply crafted requests that may, under exceptional circum...

How severe is CVE-2026-33521?

CVE-2026-33521 has been rated HIGH with a CVSS base score of 7.5/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2026-33521?

Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.