CVE-2023-28931Network attack vector

Administrator-level stored script execution

Published Aug 8, 2023 · Updated Apr 28, 2026

Stored XSS in Never5 Post Connector 1.0.9 and earlier allows remote authenticated users to execute scripts in visitors' browsers. Patchstack has not disclosed the affected input, storage path, or output sink that fails to neutralize the content. Administrator privileges are required to store the payload, and execution requires another user to visit the affected page, exposing that browser session to unauthorized actions and data access.

CVSS severity5.9
Medium
EPSS probability0.37%
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 Never5 Post Connector 1.0.9 and earlier allows remote authenticated users to execute scripts in visitors' browsers. Patchstack has not disclosed the affected input, storage path, or output sink that fails to neutralize the content. Administrator privileges are required to store the payload, and execution requires another user to visit the affected page, exposing that browser session to unauthorized actions and data access.

The record

CVE
CVE-2023-28931
Published
Aug 8, 2023
Updated
Apr 28, 2026
Vendor
Barry Kooij
Product
Post Connector
Classifications
CWE-79, CAPEC-592, T1059.007
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. Aug 8, 2023CVE publishedPublication date reported by the CVE source.
  2. Apr 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?

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

  1. Affected versionversion=n/a <=1.0.9

What conditions does exploitation require?

Attack vectornetwork
Required privilegesadmin

What is affected?

Barry Kooij · Post Connectorversion=n/a <=1.0.9

Published CVSS scores

5.9PatchstackCVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:L
4.8NVDCVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/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
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CAPEC-592Stored XSS
T1059.007JavaScript

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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