CVE-2026-54840Network attack vector

Unauthenticated user deletion via inverted authorization logic

Published Jun 26, 2026 · Updated Jun 26, 2026

Missing authorization in Tribulant Software Newsletters 4.13 and earlier allows remote attackers to delete WordPress users. The deleteuser function applies inverted authorization logic and omits a CSRF nonce check before deleting a selected WordPress account. No authentication or user interaction is required; the bounded consequence is account deletion rather than arbitrary code execution.

CVSS severity7.3
High
EPSS probability0.30%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Missing authorization in Tribulant Software Newsletters 4.13 and earlier allows remote attackers to delete WordPress users. The deleteuser function applies inverted authorization logic and omits a CSRF nonce check before deleting a selected WordPress account. No authentication or user interaction is required; the bounded consequence is account deletion rather than arbitrary code execution.

The record

CVE
CVE-2026-54840
Published
Jun 26, 2026
Updated
Jun 26, 2026
Vendor
Tribulant Software
Product
Newsletters
Classifications
CWE-862, CAPEC-180, T1531
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 26, 2026CVE publishedPublication date reported by the CVE source.
  2. Jun 26, 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 <=4.13 changes=[{"at":"4.14","status":"unaffected"}]

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Tribulant Software · Newslettersversion=n/a <=4.13 changes=[{"at":"4.14","status":"unaffected"}]

Published CVSS scores

7.3PatchstackCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-862Missing Authorization
CAPEC-180Exploiting Incorrectly Configured Access Control Security Levels
T1531Account Access Removal

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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