{"id":"CVE-2019-3855","title":"An integer overflow flaw which could lead to an out of bounds write was discovered in libssh2 before 1.8.1 in the way packets are read from the server","summary":"An integer overflow flaw which could lead to an out of bounds write was discovered in libssh2 before 1.8.1 in the way packets are read from the server. A remote attacker who compromises a SSH server may be able to execute code on the cli…","severity":"high","cvss":8.8,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","cwe":["CWE-190","CWE-787","CWE-190","CWE-787"],"vendor":"libssh2","product":"libssh2","affected":["libssh2 < 1.8.1","fedora = 28","fedora = 29","fedora = 30","debian_linux = 8.0","debian_linux = 9.0","ontap_select_deploy_administration_utility","enterprise_linux = 8.0","enterprise_linux_desktop = 7.0","enterprise_linux_server = 7.0","enterprise_linux_server_aus = 7.6","enterprise_linux_server_eus = 7.6","enterprise_linux_server_tus = 7.6","enterprise_linux_workstation = 7.0","leap = 42.3","xcode < 11.0","peoplesoft_enterprise_peopletools = 8.56","peoplesoft_enterprise_peopletools = 8.57"],"patched":["libssh2 1.8.1","xcode 11.0"],"published":"2019-03-21","updated":"2026-10-14","sourceUpdated":"2026-10-14T07:16:51.257","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2019-3855","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://packetstormsecurity.com/files/152136/Slackware-Security-Advisory-libssh2-Updates.html","label":"secalert@redhat.com"},{"url":"http://seclists.org/fulldisclosure/2019/Sep/42","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://access.redhat.com/errata/RHSA-2019:0679","label":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2019:1175","label":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2019:1652","label":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2019:1791","label":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2019:1943","label":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2019:2399","label":"secalert@redhat.com"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2019-3855","label":"secalert@redhat.com"},{"url":"https://lists.debian.org/debian-lts-announce/2019/03/msg00032.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/6LUNHPW64IGCASZ4JQ2J5KDXNZN53DWW/","label":"secalert@redhat.com"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/M7IF3LNHOA75O4WZWIHJLIRMA5LJUED3/","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://seclists.org/bugtraq/2019/Sep/49","label":"secalert@redhat.com"},{"url":"https://security.netapp.com/advisory/ntap-20190327-0005/","label":"secalert@redhat.com"},{"url":"https://support.apple.com/kb/HT210609","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-2019-3855.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://packetstormsecurity.com/files/152136/Slackware-Security-Advisory-libssh2-Updates.html","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://seclists.org/fulldisclosure/2019/Sep/42","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://access.redhat.com/errata/RHSA-2019:0679","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://access.redhat.com/errata/RHSA-2019:1175","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://access.redhat.com/errata/RHSA-2019:1652","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://access.redhat.com/errata/RHSA-2019:1791","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://access.redhat.com/errata/RHSA-2019:1943","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://access.redhat.com/errata/RHSA-2019:2399","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2019-3855","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.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/6LUNHPW64IGCASZ4JQ2J5KDXNZN53DWW/","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/M7IF3LNHOA75O4WZWIHJLIRMA5LJUED3/","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://seclists.org/bugtraq/2019/Sep/49","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://security.netapp.com/advisory/ntap-20190327-0005/","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://support.apple.com/kb/HT210609","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-2019-3855.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":0.09294,"epssPercentile":0.95278,"ingestedAt":"2026-10-14T07:21:04.808Z","slug":"CVE-2019-3855","body":"## Overview\n\nAn integer overflow flaw which could lead to an out of bounds write was discovered in libssh2 before 1.8.1 in the way packets are read from the server. A remote attacker who compromises a SSH server may be able to execute code on the client system when a user connects to the server.\n\n## Affected\n\n- `libssh2 < 1.8.1`\n- `fedora = 28`\n- `fedora = 29`\n- `fedora = 30`\n- `debian_linux = 8.0`\n- `debian_linux = 9.0`\n- `ontap_select_deploy_administration_utility`\n- `enterprise_linux = 8.0`\n- `enterprise_linux_desktop = 7.0`\n- `enterprise_linux_server = 7.0`\n- `enterprise_linux_server_aus = 7.6`\n- `enterprise_linux_server_eus = 7.6`\n- `enterprise_linux_server_tus = 7.6`\n- `enterprise_linux_workstation = 7.0`\n- `leap = 42.3`\n- `xcode < 11.0`\n- `peoplesoft_enterprise_peopletools = 8.56`\n- `peoplesoft_enterprise_peopletools = 8.57`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `libssh2 1.8.1`\n- `xcode 11.0`","depth":"twilight","depthScore":50,"depthScoreParts":{"impact":48.4,"likelihood":1.9,"exploitation":0,"ransomware":0},"changes":[]}