CVE-2026-38991: n/a
Cockpit versions 2. 13. 5 and earlier contain a vulnerability in the Bucket component's _isFileTypeAllowed function. This misconfiguration allows an authenticated attacker to bypass the file extension filter by using a specially crafted filename. As a result, the attacker can rename arbitrary files with a . php extension, enabling arbitrary code execution on the server. The vulnerability has a high severity rating with a CVSS score of 8. 8. No official patch or remediation guidance is currently provided by the vendor, and no known exploits are reported in the wild.
AI Analysis
Technical Summary
CVE-2026-38991 affects Cockpit 2.13.5 and earlier due to a misconfiguration in the Bucket component's _isFileTypeAllowed function. This flaw permits authenticated users to bypass extension filtering by crafting filenames that evade the filter, allowing them to rename files with a .php extension. This capability enables arbitrary code execution on the underlying server, posing a significant security risk. The vulnerability is categorized under CWE-434 (Unrestricted Upload of File with Dangerous Type). The CVSS v3.1 base score is 8.8, indicating high impact on confidentiality, integrity, and availability. No patch or official remediation level is currently documented, and the service is not cloud-hosted.
Potential Impact
An authenticated attacker can exploit this vulnerability to rename arbitrary files to have a .php extension, which can lead to arbitrary code execution on the server hosting Cockpit. This compromises the confidentiality, integrity, and availability of the affected system. There are no known exploits in the wild at this time.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, restrict authenticated user permissions to prevent unauthorized file renaming and monitor for suspicious file changes involving .php extensions. Avoid exposing the Cockpit interface to untrusted networks to reduce risk.
CVE-2026-38991: n/a
Description
Cockpit versions 2. 13. 5 and earlier contain a vulnerability in the Bucket component's _isFileTypeAllowed function. This misconfiguration allows an authenticated attacker to bypass the file extension filter by using a specially crafted filename. As a result, the attacker can rename arbitrary files with a . php extension, enabling arbitrary code execution on the server. The vulnerability has a high severity rating with a CVSS score of 8. 8. No official patch or remediation guidance is currently provided by the vendor, and no known exploits are reported in the wild.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-38991 affects Cockpit 2.13.5 and earlier due to a misconfiguration in the Bucket component's _isFileTypeAllowed function. This flaw permits authenticated users to bypass extension filtering by crafting filenames that evade the filter, allowing them to rename files with a .php extension. This capability enables arbitrary code execution on the underlying server, posing a significant security risk. The vulnerability is categorized under CWE-434 (Unrestricted Upload of File with Dangerous Type). The CVSS v3.1 base score is 8.8, indicating high impact on confidentiality, integrity, and availability. No patch or official remediation level is currently documented, and the service is not cloud-hosted.
Potential Impact
An authenticated attacker can exploit this vulnerability to rename arbitrary files to have a .php extension, which can lead to arbitrary code execution on the server hosting Cockpit. This compromises the confidentiality, integrity, and availability of the affected system. There are no known exploits in the wild at this time.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, restrict authenticated user permissions to prevent unauthorized file renaming and monitor for suspicious file changes involving .php extensions. Avoid exposing the Cockpit interface to untrusted networks to reduce risk.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mitre
- Date Reserved
- 2026-04-06T00:00:00.000Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 69f26bc7cbff5d861048aa3f
Added to database: 4/29/2026, 8:36:23 PM
Last enriched: 4/29/2026, 8:51:25 PM
Last updated: 4/29/2026, 9:40:11 PM
Views: 3
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