CVE-2021-26991Network attack vector

Unauthorized cross-origin interaction via permissive CORS policy

Published Mar 19, 2021 · Updated Aug 3, 2024

Cross-origin resource sharing weakness in NetApp Cloud Manager before 3.9.4 allows remote attackers to interact with the service. The web interface applies an insecure CORS policy to cross-origin requests, but NetApp has not disclosed the affected endpoint or exact origin-validation error. No authentication or user interaction is required; the published impact is unauthorized data modification, with no reported confidentiality or availability impact.

CVSS severity7.5
High
EPSS probability1.20%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Cross-origin resource sharing weakness in NetApp Cloud Manager before 3.9.4 allows remote attackers to interact with the service. The web interface applies an insecure CORS policy to cross-origin requests, but NetApp has not disclosed the affected endpoint or exact origin-validation error. No authentication or user interaction is required; the published impact is unauthorized data modification, with no reported confidentiality or availability impact.

The record

CVE
CVE-2021-26991
Published
Mar 19, 2021
Updated
Aug 3, 2024
Vendor
NetApp
Product
Cloud Manager
Classifications
T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 19, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=Prior to 3.9.4

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

NetApp · Cloud Managerversion=Prior to 3.9.4

Published CVSS scores

5.0NIST NVDAV:N/AC:L/Au:N/C:N/I:P/A:N
7.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1190Exploit Public-Facing Application

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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