CVE-2026-77143: CWE-862 Missing Authorization in TYPO3 Extension "Forum"
CVE-2026-77143 is a high-severity vulnerability in the TYPO3 Extension "Forum" that allows unauthorized modification of forum topics. The server-side does not verify ownership when a visitor edits a topic, enabling any visitor who knows a topic's identifier to overwrite its content without permission. Topic identifiers are publicly visible, and exploitation requires no special privileges or configuration changes. This affects versions prior to 6.2.4.
AI Analysis
Technical Summary
The TYPO3 Extension "Forum" suffers from a missing authorization check (CWE-862) in its frontend topic editing functionality. Specifically, the server does not confirm that the user requesting to modify a topic actually owns that topic. Because topic identifiers are exposed in the public forum listing, an unauthenticated visitor can submit update requests referencing any topic identifier and overwrite the topic content. This vulnerability requires no privileges or non-default configurations to exploit and affects all versions before 6.2.4.
Potential Impact
An attacker can overwrite the content of any forum topic by submitting a crafted update request with a known topic identifier. This unauthorized modification can lead to data integrity issues and potential misinformation within the forum. Since no authentication or ownership verification is performed, the vulnerability allows unauthenticated users to tamper with forum content.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, restrict access to the forum editing functionality or implement custom authorization checks to verify topic ownership on the server side.
CVE-2026-77143: CWE-862 Missing Authorization in TYPO3 Extension "Forum"
Description
CVE-2026-77143 is a high-severity vulnerability in the TYPO3 Extension "Forum" that allows unauthorized modification of forum topics. The server-side does not verify ownership when a visitor edits a topic, enabling any visitor who knows a topic's identifier to overwrite its content without permission. Topic identifiers are publicly visible, and exploitation requires no special privileges or configuration changes. This affects versions prior to 6.2.4.
CVSS v4.0
Score 8.8high
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The TYPO3 Extension "Forum" suffers from a missing authorization check (CWE-862) in its frontend topic editing functionality. Specifically, the server does not confirm that the user requesting to modify a topic actually owns that topic. Because topic identifiers are exposed in the public forum listing, an unauthenticated visitor can submit update requests referencing any topic identifier and overwrite the topic content. This vulnerability requires no privileges or non-default configurations to exploit and affects all versions before 6.2.4.
Potential Impact
An attacker can overwrite the content of any forum topic by submitting a crafted update request with a known topic identifier. This unauthorized modification can lead to data integrity issues and potential misinformation within the forum. Since no authentication or ownership verification is performed, the vulnerability allows unauthenticated users to tamper with forum content.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, restrict access to the forum editing functionality or implement custom authorization checks to verify topic ownership on the server side.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- TYPO3
- Date Reserved
- 2026-08-20T13:10:15.962Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a8d5b66acd9273b49f365d1
Added to database: 08/25/2026, 09:07:50 UTC
Last enriched: 08/25/2026, 09:22:23 UTC
Last updated: 08/25/2026, 09:22:23 UTC
Views: 6
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