CVE-2021-26587Network attack vector

Privilege escalation via undisclosed DOM cross-site scripting

Published Sep 27, 2021 · Updated Aug 3, 2024

DOM-based cross-site scripting in HPE StoreOnce Software 4.2.3 and earlier allows remote authenticated users to elevate privileges. HPE has not published the affected client-side code, DOM source, or unsafe sink that processes attacker-controlled content. Exploitation requires authenticated access and user interaction; successful script execution can expose or alter data and interrupt appliance service.

CVSS severity6.5
Medium
EPSS probability0.50%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

DOM-based cross-site scripting in HPE StoreOnce Software 4.2.3 and earlier allows remote authenticated users to elevate privileges. HPE has not published the affected client-side code, DOM source, or unsafe sink that processes attacker-controlled content. Exploitation requires authenticated access and user interaction; successful script execution can expose or alter data and interrupt appliance service.

The record

CVE
CVE-2021-26587
Published
Sep 27, 2021
Updated
Aug 3, 2024
Vendor
Hewlett Packard Enterprise (HPE)
Product
HPE StoreOnce Software
Classifications
CWE-79, T1203
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Sep 27, 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

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

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

  1. Affected versionversion=Firmware version: 4.2.3 and earlier
  2. Affected versionversion=FW version: 4.2.3 and earlier

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Hewlett Packard Enterprise (HPE) · HPE StoreOnce Softwareversion=Firmware version: 4.2.3 and earlier; version=FW version: 4.2.3 and earlier

Published CVSS scores

6.0NIST NVDAV:N/AC:M/Au:S/C:P/I:P/A:P
6.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:L

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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1203Exploitation for Client Execution

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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