CVE-2019-3863 HIGH

CVE-2019-3863

Vendor The Libssh2 Project
Product libssh2
Weakness CWE-190
Published March 25, 2019
Last update December 19, 2025

CVSS base score

7.5/10
Attack vector Network
Attack complexity High
Privileges required None
User interaction Required
Confidentiality High
Integrity High

CVSS vector

CVSS:3.0/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H

What the vulnerability does

01Description

A flaw was found in libssh2 before 1.8.1 creating a vulnerability on the SSH client side. A server could send a multiple keyboard interactive response messages whose total length are greater than unsigned char max characters. This value is used by the SSH client as an index to copy memory causing in an out of bounds memory write error.

Key dates

02Disclosure timeline

March 25, 2019 CVE published
December 19, 2025 Record updated