Cerberus FTP Server: Insecure Preserved Inherited Permissions
CVE-2026-6265 is a high-severity insecure preserved inherited permissions vulnerability in Cerberus FTP Server from Cerberus, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. Affected Cerberus FTP Server versions: 2025.4.2 and earlier. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.26% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update FTP Server to 2026.1 or a later version.
- Read the advisory on labs.reversec.com for workarounds and exact fixed builds.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Cerberus | Cerberus FTP Server | 2025.4.2 and earlier | Not stated |
| Cerberusftp | FTP Server | before 2026.1 | 2026.1 |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- LowA basic user account is enough.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 4.0 | 7.3 | High | CNA |
| CVSS 3.1 | 8.8 | High | NVD |
Official description
Insecure preserved inherited permissions vulnerability in Cerberus FTP Server on Windows allows Privilege Escalation.This issue has been resolved in Cerberus FTP Server: 2026.1
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Insecure Preserved Inherited Permissions
A product inherits a set of insecure permissions for an object, e.g. when copying from an archive file, without user awareness or involvement.
How developers prevent this class of flaw
- Very carefully manage the setting, management, and handling of privileges. Explicitly manage trust zones in the software.
- Compartmentalize the system to have safe areas where trust boundaries can be unambiguously drawn. Do not allow sensitive data to go outside of the trust boundary and always be careful when interfacing with a compartment outside of the safe area. Ensure that appropriate compartmentalization is built into the system design, and the compartmentalization allows for and reinforces privilege separation functionality. Architects and designers should rely on the principle of least privilege to decide the appropriate time to use privileges and the time to drop privileges.
More Insecure Preserved Inherited Permissions vulnerabilities (CWE-278)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: poc, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
- cerberusftp.com/releasenotes/Release Notes
Other vulnerabilities in Cerberus FTP Server
- 7.1 High severity
- 7.5 High severity
Recent Insecure Preserved Inherited Permissions vulnerabilities
- 9.8 Critical severity
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