CVE-2023-43901Public exploitNetwork attack vector

Unauthenticated user modification via AdHoc creation

Published Nov 14, 2023 · Updated Aug 28, 2026

Incorrect access control in EMSigner 2.8.7 allows remote attackers to modify registered users' names and privileges. The /eMsecure/Users/AdhocUser endpoint processes a supplied Name and registered email address as an update to the matching user record. Knowledge of a registered email address is sufficient, and the demonstrated consequence is integrity loss through username changes and privilege reduction.

CVSS severity5.9
Medium
EPSS probability0.47%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Incorrect access control in EMSigner 2.8.7 allows remote attackers to modify registered users' names and privileges. The /eMsecure/Users/AdhocUser endpoint processes a supplied Name and registered email address as an update to the matching user record. Knowledge of a registered email address is sufficient, and the demonstrated consequence is integrity loss through username changes and privilege reduction.

The record

CVE
CVE-2023-43901
Published
Nov 14, 2023
Updated
Aug 28, 2026
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-284, T1098
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Nov 14, 2023CVE publishedPublication date reported by the CVE source.
  2. Aug 28, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

5.9NIST NVDCVSS:3.1/AV:N/AC:H/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.

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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 exploitPublished

Weakness, pattern, technique

CWE-284Improper Access Control
T1098Account Manipulation

Public exploit references

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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