What is the CVSS score of CVE-2021-22968?

CVE-2021-22968 has a CVSS 3.1 base score of 7.2 (High). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H. EPSS exploitation probability: 3.1%.

Is there a public PoC exploit available for CVE-2021-22968?

Yes, a public proof-of-concept exploit is available for CVE-2021-22968. Prioritise patching immediately. EPSS: 3.1%.

Is there a patch available for CVE-2021-22968?

Yes, a patch is available for CVE-2021-22968. Update the affected software to the latest version immediately.

PHP CVE-2021-22968

HIGH

PHP Remote File Inclusion (CWE-98)

2021-11-19 support@hackerone.com

LFI RCE PHP File Upload Concrete Cms

7.2

CVSS 3.1 · NVD

Severity by source

NVD PRIMARY

7.2 HIGH

AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H

Attack Vector

Network

Attack Complexity

Low

Privileges Required

High

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Lifecycle Timeline

CVE Published

Nov 19, 2021 - 19:15 nvd

HIGH 7.2

DescriptionNVD

A bypass of adding remote files in Concrete CMS (previously concrete5) File Manager leads to remote code execution in Concrete CMS (concrete5) versions 8.5.6 and below.The external file upload feature stages files in the public directory even if they have disallowed file extensions. They are stored in a directory with a random name, but it's possible to stall the uploads and brute force the directory name. You have to be an admin with the ability to upload files, but this bug gives you the ability to upload restricted file types and execute them depending on server configuration.To fix this, a check for allowed file extensions was added before downloading files to a tmp directory.Concrete CMS Security Team gave this a CVSS v3.1 score of 5.4 AV:N/AC:H/PR:H/UI:R/S:C/C:N/I:H/A:NThis fix is also in Concrete version 9.0.0

AnalysisAI

A bypass of adding remote files in Concrete CMS (previously concrete5) File Manager leads to remote code execution in Concrete CMS (concrete5) versions 8.5.6 and below.The external file upload. Rated high severity (CVSS 7.2), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.

Technical ContextAI

This vulnerability is classified under CWE-98. A bypass of adding remote files in Concrete CMS (previously concrete5) File Manager leads to remote code execution in Concrete CMS (concrete5) versions 8.5.6 and below.The external file upload feature stages files in the public directory even if they have disallowed file extensions. They are stored in a directory with a random name, but it's possible to stall the uploads and brute force the directory name. You have to be an admin with the ability to upload files, but this bug gives you the ability to upload restricted file types and execute them depending on server configuration.To fix this, a check for allowed file extensions was added before downloading files to a tmp directory.Concrete CMS Security Team gave this a CVSS v3.1 score of 5.4 AV:N/AC:H/PR:H/UI:R/S:C/C:N/I:H/A:NThis fix is also in Concrete version 9.0.0 Affected products include: Concretecms Concrete Cms. Version information: version 9.0.0.

RemediationAI

No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.