Medium severity · published Jul 25, 2025
CVE-2025-5449
Libssh: integer overflow in libssh sftp server packet length validation leading to denial of service
6.5
CVSS
1%
EPSS
No
On KEV
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 vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.0% · higher than 64% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
LI
Libssh · Libssh
0.11.0; 0.11.1 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-5449
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-5449
Third Party Advisory
https://access.redhat.com/security/cve/CVE-2025-5449
Issue Tracking
https://bugzilla.redhat.com/show_bug.cgi?id=2369705
Patch
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
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