CVE-2021-32539Network attack vector

Stored XSS via unsanitized calendar event fields

Published May 28, 2021 · Updated Sep 16, 2024

Stored XSS in the calendar add-event function in Hundred Plus 101EIP RELEASE_200925 allows remote authenticated users to inject JavaScript. Specific calendar event fields accept special characters without filtering and store attacker-supplied script for later rendering. An authenticated user must submit the payload and another user must view the saved event, allowing script execution in that viewer’s browser context.

CVSS severity5.4
Medium
EPSS probability0.59%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stored XSS in the calendar add-event function in Hundred Plus 101EIP RELEASE_200925 allows remote authenticated users to inject JavaScript. Specific calendar event fields accept special characters without filtering and store attacker-supplied script for later rendering. An authenticated user must submit the payload and another user must view the saved event, allowing script execution in that viewer’s browser context.

The record

CVE
CVE-2021-32539
Published
May 28, 2021
Updated
Sep 16, 2024
Vendor
Hundred Plus
Product
101EIP
Classifications
CWE-79, T1059.007
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. May 28, 2021CVE publishedPublication date reported by the CVE source.
  2. Sep 16, 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=RELEASE_200925

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Hundred Plus · 101EIPversion=RELEASE_200925

Published CVSS scores

5.4TWCERT/CCCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
3.5NVDAV:N/AC:M/Au:S/C:N/I:P/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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1059.007Command and Scripting Interpreter: JavaScript/JScript

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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