--- id: CVE-2019-3859 title: >- An out of bounds read flaw was discovered in libssh2 before 1.8.1 in the _libssh2_packet_require and _libssh2_packet_requirev functions summary: >- An out of bounds read flaw was discovered in libssh2 before 1.8.1 in the _libssh2_packet_require and _libssh2_packet_requirev functions. A remote attacker who compromises a SSH server may be able to cause a Denial of Service or read data… severity: critical cvss: 9.1 cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H' cwe: - CWE-125 - CWE-125 - CWE-125 vendor: libssh2 product: libssh2 affected: - libssh2 < 1.8.1 - fedora = 28 - fedora = 29 - debian_linux = 8.0 - debian_linux = 9.0 - ontap_select_deploy_administration_utility - leap = 15.0 - leap = 42.3 patched: - libssh2 1.8.1 published: '2019-03-21' updated: '2026-10-14' sourceUpdated: '2026-10-14T07:16:52.390' source: NVD sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2019-3859' references: - url: 'http://lists.opensuse.org/opensuse-security-announce/2019-03/msg00040.html' label: secalert@redhat.com - url: 'http://lists.opensuse.org/opensuse-security-announce/2019-04/msg00003.html' label: secalert@redhat.com - url: 'http://lists.opensuse.org/opensuse-security-announce/2019-04/msg00102.html' label: secalert@redhat.com - url: 'http://lists.opensuse.org/opensuse-security-announce/2019-04/msg00103.html' label: secalert@redhat.com - url: >- http://packetstormsecurity.com/files/152136/Slackware-Security-Advisory-libssh2-Updates.html label: secalert@redhat.com - url: 'http://www.openwall.com/lists/oss-security/2019/03/18/3' label: secalert@redhat.com - url: 'http://www.securityfocus.com/bid/107485' label: secalert@redhat.com - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2019-3859' label: secalert@redhat.com - url: 'https://lists.debian.org/debian-lts-announce/2019/03/msg00032.html' label: secalert@redhat.com - url: 'https://lists.debian.org/debian-lts-announce/2019/04/msg00006.html' label: secalert@redhat.com - url: 'https://lists.debian.org/debian-lts-announce/2019/07/msg00024.html' label: secalert@redhat.com - url: >- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5DK6VO2CEUTAJFYIKWNZKEKYMYR3NO2O/ label: secalert@redhat.com - url: >- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/XCWEA5ZCLKRDUK62QVVYMFWLWKOPX3LO/ label: secalert@redhat.com - url: 'https://seclists.org/bugtraq/2019/Apr/25' label: secalert@redhat.com - url: 'https://seclists.org/bugtraq/2019/Mar/25' label: secalert@redhat.com - url: 'https://security.netapp.com/advisory/ntap-20190327-0005/' label: secalert@redhat.com - url: >- https://www.broadcom.com/support/fibre-channel-networking/security-advisories/brocade-security-advisory-2019-767 label: secalert@redhat.com - url: 'https://www.debian.org/security/2019/dsa-4431' label: secalert@redhat.com - url: 'https://www.libssh2.org/CVE-2019-3859.html' label: secalert@redhat.com - url: >- https://www.oracle.com/technetwork/security-advisory/cpuoct2019-5072832.html label: secalert@redhat.com - url: 'http://lists.opensuse.org/opensuse-security-announce/2019-03/msg00040.html' label: af854a3a-2127-422b-91ae-364da2661108 - url: 'http://lists.opensuse.org/opensuse-security-announce/2019-04/msg00003.html' label: af854a3a-2127-422b-91ae-364da2661108 - url: 'http://lists.opensuse.org/opensuse-security-announce/2019-04/msg00102.html' label: af854a3a-2127-422b-91ae-364da2661108 - url: 'http://lists.opensuse.org/opensuse-security-announce/2019-04/msg00103.html' label: af854a3a-2127-422b-91ae-364da2661108 - url: >- http://packetstormsecurity.com/files/152136/Slackware-Security-Advisory-libssh2-Updates.html label: af854a3a-2127-422b-91ae-364da2661108 - url: 'http://www.openwall.com/lists/oss-security/2019/03/18/3' label: af854a3a-2127-422b-91ae-364da2661108 - url: 'http://www.securityfocus.com/bid/107485' label: af854a3a-2127-422b-91ae-364da2661108 - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2019-3859' label: af854a3a-2127-422b-91ae-364da2661108 - url: 'https://lists.debian.org/debian-lts-announce/2019/03/msg00032.html' label: af854a3a-2127-422b-91ae-364da2661108 - url: 'https://lists.debian.org/debian-lts-announce/2019/04/msg00006.html' label: af854a3a-2127-422b-91ae-364da2661108 - url: 'https://lists.debian.org/debian-lts-announce/2019/07/msg00024.html' label: af854a3a-2127-422b-91ae-364da2661108 - url: >- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5DK6VO2CEUTAJFYIKWNZKEKYMYR3NO2O/ label: af854a3a-2127-422b-91ae-364da2661108 - url: >- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/XCWEA5ZCLKRDUK62QVVYMFWLWKOPX3LO/ label: af854a3a-2127-422b-91ae-364da2661108 - url: 'https://seclists.org/bugtraq/2019/Apr/25' label: af854a3a-2127-422b-91ae-364da2661108 - url: 'https://seclists.org/bugtraq/2019/Mar/25' label: af854a3a-2127-422b-91ae-364da2661108 - url: 'https://security.netapp.com/advisory/ntap-20190327-0005/' label: af854a3a-2127-422b-91ae-364da2661108 - url: >- https://www.broadcom.com/support/fibre-channel-networking/security-advisories/brocade-security-advisory-2019-767 label: af854a3a-2127-422b-91ae-364da2661108 - url: 'https://www.debian.org/security/2019/dsa-4431' label: af854a3a-2127-422b-91ae-364da2661108 - url: 'https://www.libssh2.org/CVE-2019-3859.html' label: af854a3a-2127-422b-91ae-364da2661108 - url: >- https://www.oracle.com/technetwork/security-advisory/cpuoct2019-5072832.html label: af854a3a-2127-422b-91ae-364da2661108 - url: 'https://cert-portal.siemens.com/productcert/html/ssa-398330.html' label: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e tags: - nvd epss: 0.06275 epssPercentile: 0.93436 ingestedAt: '2026-10-14T07:21:04.807Z' --- ## Overview An out of bounds read flaw was discovered in libssh2 before 1.8.1 in the _libssh2_packet_require and _libssh2_packet_requirev functions. A remote attacker who compromises a SSH server may be able to cause a Denial of Service or read data in the client memory. ## Affected - `libssh2 < 1.8.1` - `fedora = 28` - `fedora = 29` - `debian_linux = 8.0` - `debian_linux = 9.0` - `ontap_select_deploy_administration_utility` - `leap = 15.0` - `leap = 42.3` ## Remediation Upgrade past the affected range: - `libssh2 1.8.1`