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Vulnerability record · CVE-2019-3863 · published 25 March 2019

CVE-2019-3863: Libssh2 integer overflow vulnerability

LLibssh2 · Libssh2

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.

8.8 CVSS 3.0 High EPSS 3.4% · top 11.5% CWE-190 · Integer overflowCWE-787 · Out-of-bounds write
8.8CVSS 3.0 base score, v2 6.8
3.4%EPSS exploitation probability, 30 days
NoNot in CISA KEV
10Affected product versions listed by NVD
32References
17 Jun 2026Last modified by NVD

Description

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.

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

Affected products

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

References

LinkTags
http://lists.opensuse.org/opensuse-security-announce/2019-03/msg00040.html Mailing ListThird Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2019-04/msg00003.html Third Party Advisory
https://access.redhat.com/errata/RHSA-2019:0679 Third Party Advisory
https://access.redhat.com/errata/RHSA-2019:1175
https://access.redhat.com/errata/RHSA-2019:1652
https://access.redhat.com/errata/RHSA-2019:1791
https://access.redhat.com/errata/RHSA-2019:1943
https://access.redhat.com/errata/RHSA-2019:2399
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2019-3863 Issue TrackingPatchThird Party Advisory
https://lists.debian.org/debian-lts-announce/2019/03/msg00032.html Mailing ListThird Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5DK6VO2CEUTAJFYIKWNZKEK
https://seclists.org/bugtraq/2019/Apr/25
https://security.netapp.com/advisory/ntap-20190327-0005/ Third Party Advisory
https://www.debian.org/security/2019/dsa-4431
https://www.libssh2.org/CVE-2019-3863.html PatchVendor Advisory
https://www.oracle.com/technetwork/security-advisory/cpuoct2019-5072832.html
http://lists.opensuse.org/opensuse-security-announce/2019-03/msg00040.html Mailing ListThird Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2019-04/msg00003.html Third Party Advisory
https://access.redhat.com/errata/RHSA-2019:0679 Third Party Advisory
https://access.redhat.com/errata/RHSA-2019:1175
https://access.redhat.com/errata/RHSA-2019:1652
https://access.redhat.com/errata/RHSA-2019:1791
https://access.redhat.com/errata/RHSA-2019:1943
https://access.redhat.com/errata/RHSA-2019:2399
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2019-3863 Issue TrackingPatchThird Party Advisory
https://lists.debian.org/debian-lts-announce/2019/03/msg00032.html Mailing ListThird Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5DK6VO2CEUTAJFYIKWNZKEK
https://seclists.org/bugtraq/2019/Apr/25
https://security.netapp.com/advisory/ntap-20190327-0005/ Third Party Advisory
https://www.debian.org/security/2019/dsa-4431
https://www.libssh2.org/CVE-2019-3863.html PatchVendor Advisory
https://www.oracle.com/technetwork/security-advisory/cpuoct2019-5072832.html

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Source: NIST National Vulnerability Database (record CVE-2019-3863), CISA KEV, FIRST EPSS (scores of 2026-09-27). This page is refreshed as NVD updates the record.