A missing allocation check in sftp server processing read requests may cause a NULL dereference on low-memory conditions. The malicious client can request up to 4GB SFTP reads, causing allocation of up to 4GB buffers, which was not being checked for failure. This will likely crash the authenticated user's sftp server connection (if implemented as forking as recommended). For thread-based servers, this might also cause DoS for legitimate users.

Given this code is not in any released versions, no security releases have been issued.
Advisories
Source ID Title
EUVD EUVD EUVD-2023-44252 A missing allocation check in sftp server processing read requests may cause a NULL dereference on low-memory conditions. The malicious client can request up to 4GB SFTP reads, causing allocation of up to 4GB buffers, which was not being checked for failure. This will likely crash the authenticated user's sftp server connection (if implemented as forking as recommended). For thread-based servers, this might also cause DoS for legitimate users. Given this code is not in any released versions, no security releases have been issued.
Fixes

Solution

No solution given by the vendor.


Workaround

The SFTP server implementation is based on callbacks so you can rewrite the sftp_channel_default_data_callback() to provide additional checks. [1] https://gitlab.com/libssh/libssh-mirror/-/blob/master/examples/sample_sftpserver.c#L330

History

Thu, 26 Sep 2024 20:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


cve-icon MITRE

Status: PUBLISHED

Assigner: redhat

Published:

Updated: 2024-09-26T20:04:43.251Z

Reserved: 2023-07-10T18:21:21.431Z

Link: CVE-2023-3603

cve-icon Vulnrichment

Updated: 2024-08-02T07:01:56.718Z

cve-icon NVD

Status : Modified

Published: 2023-07-21T20:15:16.587

Modified: 2024-11-21T08:17:38.737

Link: CVE-2023-3603

cve-icon Redhat

Severity : Low

Publid Date: 2023-07-10T00:00:00Z

Links: CVE-2023-3603 - Bugzilla

cve-icon OpenCVE Enrichment

No data.