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Vulnerability record · CVE-2025-5449 · published 25 July 2025

CVE-2025-5449: Libssh integer overflow vulnerability

Libssh · Libssh

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.

6.5 CVSS 3.1 Medium EPSS 0.88% · top 42.7% CWE-190 · Integer overflow
6.5CVSS 3.1 base score
0.88%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
8References
31 Aug 2026Last modified by NVD

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.

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

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://access.redhat.com/security/cve/CVE-2025-5449 Third Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2369705 Issue TrackingThird Party Advisory
https://git.libssh.org/projects/libssh.git/commit/?h=stable-0.11&id=261612179f740bc62ba363d98b3bd5e5573a811f Patch
https://git.libssh.org/projects/libssh.git/commit/?h=stable-0.11&id=3443aec90188d6aab9282afc80a81df5ab72c4da Patch
https://git.libssh.org/projects/libssh.git/commit/?h=stable-0.11&id=5504ff40515439a5fecbb17da7483000c4d12eb7 Patch
https://git.libssh.org/projects/libssh.git/commit/?h=stable-0.11&id=78485f446af9b30e37eb8f177b81940710d54496 Patch
https://git.libssh.org/projects/libssh.git/commit/?h=stable-0.11&id=f79ec51b7fd519dbc5737a7ba826e3ed093f6ceb Patch
https://www.libssh.org/security/advisories/CVE-2025-5449.txt Third Party Advisory

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2025-5449), CISA KEV, FIRST EPSS (scores of 2026-09-27). This page is refreshed as NVD updates the record.