CVE-2025-5449

Libssh: integer overflow in libssh sftp server packet length validation leading to denial of service

Published Jul 25, 2025 CVSS 3.1 · 6.5 Medium EPSS 1.0% KEV · Not listed
Description
A flaw was found in the SFTP server message decoding logic of libssh. The issue occurs due to an incorrect packet length check that allows an integer overflow when handling large payload sizes on 32-bit systems. This issue leads to failed memory allocation and causes the server process to crash, resulting in a denial of service.

Remediation

Vendor Workaround

Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.

Tracking

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Advisories

Source ID Title
EUVD EUVD EUVD-2025-22738 A flaw was found in the SFTP server message decoding logic of libssh. The issue occurs due to an incorrect packet length check that allows an integer overflow when handling large payload sizes on 32-bit systems. This issue leads to failed memory allocation and causes the server process to crash, resulting in a denial of service.
Ubuntu USN Ubuntu USN USN-7619-1 libssh vulnerabilities
History
Type Values Removed Values Added
First Time appeared Redhat rhel Els
CPEs cpe:/o:redhat:enterprise_linux:10
cpe:/o:redhat:enterprise_linux:6
cpe:/o:redhat:enterprise_linux:7
cpe:/o:redhat:enterprise_linux:8
cpe:/o:redhat:enterprise_linux:9
cpe:/a:redhat:enterprise_linux:10
cpe:/a:redhat:enterprise_linux:8
cpe:/a:redhat:enterprise_linux:9
cpe:/o:redhat:rhel_els:6
cpe:/o:redhat:rhel_els:7
Vendors & Products Redhat rhel Els
Type Values Removed Values Added
CPEs cpe:/o:redhat:rhivos:1
Vendors & Products Redhat rhivos
Type Values Removed Values Added
First Time appeared Redhat rhivos
CPEs cpe:/o:redhat:rhivos:1
Vendors & Products Redhat rhivos
Type Values Removed Values Added
Metrics cvssV3_1

{'score': 4.3, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L'}

cvssV3_1

{'score': 6.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}

Type Values Removed Values Added
First Time appeared Libssh
Libssh libssh
CPEs cpe:2.3:a:libssh:libssh:0.11.0:*:*:*:*:*:*:*
cpe:2.3:a:libssh:libssh:0.11.1:*:*:*:*:*:*:*
Vendors & Products Libssh
Libssh libssh
Type Values Removed Values Added
Metrics ssvc

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

Type Values Removed Values Added
Title libssh: Integer Overflow in libssh SFTP Server Packet Length Validation Leading to Denial of Service Libssh: integer overflow in libssh sftp server packet length validation leading to denial of service
First Time appeared Redhat
Redhat enterprise Linux
Redhat openshift
CPEs cpe:/a:redhat:openshift:4
cpe:/o:redhat:enterprise_linux:10
cpe:/o:redhat:enterprise_linux:6
cpe:/o:redhat:enterprise_linux:7
cpe:/o:redhat:enterprise_linux:8
cpe:/o:redhat:enterprise_linux:9
Vendors & Products Redhat
Redhat enterprise Linux
Redhat openshift
References
Type Values Removed Values Added
Description A flaw was found in the SFTP server message decoding logic of libssh. The issue occurs due to an incorrect packet length check that allows an integer overflow when handling large payload sizes on 32-bit systems. This issue leads to failed memory allocation and causes the server process to crash, resulting in a denial of service.
Title libssh: Integer Overflow in libssh SFTP Server Packet Length Validation Leading to Denial of Service
Weaknesses CWE-190
References
Metrics threat_severity

None

cvssV3_1

{'score': 4.3, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L'}

threat_severity

Moderate

Weaknesses

Sources

Status
PUBLISHED
Assigner
redhat
Published
Updated
Nov 5, 2026, 3:37 PM
Reserved
Jun 2, 2025, 7:10 AM
Status
Modified
Published
Jul 25, 2025, 6:15 PM
Modified
Nov 5, 2026, 4:17 PM
Severity
Moderate
Public date
Jun 24, 2025, 12:00 AM