{"id":"UBUNTU-CVE-2020-10188","details":"utility.c in telnetd in netkit telnet through 0.17 allows remote attackers to execute arbitrary code via short writes or urgent data, because of a buffer overflow involving the netclear and nextitem functions.","modified":"2026-05-20T16:04:07.478194153Z","published":"2020-03-06T15:15:00Z","related":["USN-5048-1","USN-5048-2","USN-7781-1"],"upstream":["CVE-2020-10188"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2020-10188"},{"type":"REPORT","url":"https://appgateresearch.blogspot.com/2020/02/bravestarr-fedora-31-netkit-telnetd_28.html"},{"type":"REPORT","url":"https://github.com/krb5/krb5-appl/blob/d00cd671dfe945791b33d4f1f6a5c57ae1667ef8/telnet/telnetd/utility.c#L205-L216"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-5048-1"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-5048-2"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2020-10188"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-7781-1"}],"affected":[{"package":{"name":"inetutils","ecosystem":"Ubuntu:Pro:14.04:LTS","purl":"pkg:deb/ubuntu/inetutils?arch=source&distro=esm-infra-legacy%2Ftrusty"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2:1.9.2-1ubuntu0.1~esm2"}]}],"versions":["2:1.9.1.306-0a482-1","2:1.9.1.363-bbc1-1","2:1.9.2-1","2:1.9.2-1ubuntu0.1~esm1"],"ecosystem_specific":{"binaries":[{"binary_name":"inetutils-ftp","binary_version":"2:1.9.2-1ubuntu0.1~esm2"},{"binary_name":"inetutils-ftpd","binary_version":"2:1.9.2-1ubuntu0.1~esm2"},{"binary_name":"inetutils-inetd","binary_version":"2:1.9.2-1ubuntu0.1~esm2"},{"binary_name":"inetutils-ping","binary_version":"2:1.9.2-1ubuntu0.1~esm2"},{"binary_name":"inetutils-syslogd","binary_version":"2:1.9.2-1ubuntu0.1~esm2"},{"binary_name":"inetutils-talk","binary_version":"2:1.9.2-1ubuntu0.1~esm2"},{"binary_name":"inetutils-talkd","binary_version":"2:1.9.2-1ubuntu0.1~esm2"},{"binary_name":"inetutils-telnet","binary_version":"2:1.9.2-1ubuntu0.1~esm2"},{"binary_name":"inetutils-telnetd","binary_version":"2:1.9.2-1ubuntu0.1~esm2"},{"binary_name":"inetutils-tools","binary_version":"2:1.9.2-1ubuntu0.1~esm2"},{"binary_name":"inetutils-traceroute","binary_version":"2:1.9.2-1ubuntu0.1~esm2"}],"availability":"Available with Ubuntu Pro with Legacy support add-on: https://ubuntu.com/pro"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2020/UBUNTU-CVE-2020-10188.json"}},{"package":{"name":"inetutils","ecosystem":"Ubuntu:Pro:16.04:LTS","purl":"pkg:deb/ubuntu/inetutils?arch=source&distro=esm-apps%2Fxenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2:1.9.4-1ubuntu0.1~esm1"}]}],"versions":["2:1.9.4-1","2:1.9.4-1build1"],"ecosystem_specific":{"binaries":[{"binary_name":"inetutils-ftp","binary_version":"2:1.9.4-1ubuntu0.1~esm1"},{"binary_name":"inetutils-ftpd","binary_version":"2:1.9.4-1ubuntu0.1~esm1"},{"binary_name":"inetutils-inetd","binary_version":"2:1.9.4-1ubuntu0.1~esm1"},{"binary_name":"inetutils-ping","binary_version":"2:1.9.4-1ubuntu0.1~esm1"},{"binary_name":"inetutils-syslogd","binary_version":"2:1.9.4-1ubuntu0.1~esm1"},{"binary_name":"inetutils-talk","binary_version":"2:1.9.4-1ubuntu0.1~esm1"},{"binary_name":"inetutils-talkd","binary_version":"2:1.9.4-1ubuntu0.1~esm1"},{"binary_name":"inetutils-telnet","binary_version":"2:1.9.4-1ubuntu0.1~esm1"},{"binary_name":"inetutils-telnetd","binary_version":"2:1.9.4-1ubuntu0.1~esm1"},{"binary_name":"inetutils-tools","binary_version":"2:1.9.4-1ubuntu0.1~esm1"},{"binary_name":"inetutils-traceroute","binary_version":"2:1.9.4-1ubuntu0.1~esm1"}],"availability":"Available with Ubuntu Pro: https://ubuntu.com/pro"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2020/UBUNTU-CVE-2020-10188.json"}},{"package":{"name":"netkit-telnet-ssl","ecosystem":"Ubuntu:16.04:LTS","purl":"pkg:deb/ubuntu/netkit-telnet-ssl?arch=source&distro=xenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.17.40+0.2-1"],"ecosystem_specific":{"binaries":[{"binary_name":"telnet-ssl","binary_version":"0.17.40+0.2-1"},{"binary_name":"telnetd-ssl","binary_version":"0.17.40+0.2-1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2020/UBUNTU-CVE-2020-10188.json"}},{"package":{"name":"inetutils","ecosystem":"Ubuntu:18.04:LTS","purl":"pkg:deb/ubuntu/inetutils?arch=source&distro=bionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2:1.9.4-3ubuntu0.1"}]}],"versions":["2:1.9.4-2build1","2:1.9.4-3"],"ecosystem_specific":{"binaries":[{"binary_name":"inetutils-ftp","binary_version":"2:1.9.4-3ubuntu0.1"},{"binary_name":"inetutils-ftpd","binary_version":"2:1.9.4-3ubuntu0.1"},{"binary_name":"inetutils-inetd","binary_version":"2:1.9.4-3ubuntu0.1"},{"binary_name":"inetutils-ping","binary_version":"2:1.9.4-3ubuntu0.1"},{"binary_name":"inetutils-syslogd","binary_version":"2:1.9.4-3ubuntu0.1"},{"binary_name":"inetutils-talk","binary_version":"2:1.9.4-3ubuntu0.1"},{"binary_name":"inetutils-talkd","binary_version":"2:1.9.4-3ubuntu0.1"},{"binary_name":"inetutils-telnet","binary_version":"2:1.9.4-3ubuntu0.1"},{"binary_name":"inetutils-telnetd","binary_version":"2:1.9.4-3ubuntu0.1"},{"binary_name":"inetutils-tools","binary_version":"2:1.9.4-3ubuntu0.1"},{"binary_name":"inetutils-traceroute","binary_version":"2:1.9.4-3ubuntu0.1"}],"availability":"No 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required"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2020/UBUNTU-CVE-2020-10188.json"}},{"package":{"name":"netkit-telnet-ssl","ecosystem":"Ubuntu:18.04:LTS","purl":"pkg:deb/ubuntu/netkit-telnet-ssl?arch=source&distro=bionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.17.41+0.2-3","0.17.41+0.2-3build1"],"ecosystem_specific":{"binaries":[{"binary_name":"telnet-ssl","binary_version":"0.17.41+0.2-3build1"},{"binary_name":"telnetd-ssl","binary_version":"0.17.41+0.2-3build1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2020/UBUNTU-CVE-2020-10188.json"}},{"package":{"name":"inetutils","ecosystem":"Ubuntu:20.04:LTS","purl":"pkg:deb/ubuntu/inetutils?arch=source&distro=focal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2:1.9.4-11ubuntu0.1"}]}],"versions":["2:1.9.4-10build1","2:1.9.4-11"],"ecosystem_specific":{"binaries":[{"binary_name":"inetutils-ftp","binary_version":"2:1.9.4-11ubuntu0.1"},{"binary_name":"inetutils-ftpd","binary_version":"2:1.9.4-11ubuntu0.1"},{"binary_name":"inetutils-inetd","binary_version":"2:1.9.4-11ubuntu0.1"},{"binary_name":"inetutils-ping","binary_version":"2:1.9.4-11ubuntu0.1"},{"binary_name":"inetutils-syslogd","binary_version":"2:1.9.4-11ubuntu0.1"},{"binary_name":"inetutils-talk","binary_version":"2:1.9.4-11ubuntu0.1"},{"binary_name":"inetutils-talkd","binary_version":"2:1.9.4-11ubuntu0.1"},{"binary_name":"inetutils-telnet","binary_version":"2:1.9.4-11ubuntu0.1"},{"binary_name":"inetutils-telnetd","binary_version":"2:1.9.4-11ubuntu0.1"},{"binary_name":"inetutils-tools","binary_version":"2:1.9.4-11ubuntu0.1"},{"binary_name":"inetutils-traceroute","binary_version":"2:1.9.4-11ubuntu0.1"}],"availability":"No subscription required"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2020/UBUNTU-CVE-2020-10188.json"}},{"package":{"name":"netkit-telnet-ssl","ecosystem":"Ubuntu:20.04:LTS","purl":"pkg:deb/ubuntu/netkit-telnet-ssl?arch=source&distro=focal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.17.41+0.2-3.2","0.17.41+0.2-3.2build1"],"ecosystem_specific":{"binaries":[{"binary_name":"telnet-ssl","binary_version":"0.17.41+0.2-3.2build1"},{"binary_name":"telnetd-ssl","binary_version":"0.17.41+0.2-3.2build1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2020/UBUNTU-CVE-2020-10188.json"}},{"package":{"name":"netkit-telnet-ssl","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/netkit-telnet-ssl?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.17.41+0.2-3.3build1","0.17.41+0.2-3.3build2"],"ecosystem_specific":{"binaries":[{"binary_name":"telnet-ssl","binary_version":"0.17.41+0.2-3.3build2"},{"binary_name":"telnetd-ssl","binary_version":"0.17.41+0.2-3.3build2"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2020/UBUNTU-CVE-2020-10188.json"}},{"package":{"name":"netkit-telnet-ssl","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/netkit-telnet-ssl?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.17.41+really0.17-4","0.17.41+really0.17-4build1","0.17.41+really0.17-4build2"],"ecosystem_specific":{"binaries":[{"binary_name":"telnet-ssl","binary_version":"0.17.41+really0.17-4build2"},{"binary_name":"telnetd-ssl","binary_version":"0.17.41+really0.17-4build2"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2020/UBUNTU-CVE-2020-10188.json"}},{"package":{"name":"netkit-telnet-ssl","ecosystem":"Ubuntu:25.10","purl":"pkg:deb/ubuntu/netkit-telnet-ssl?arch=source&distro=questing"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.17.41+really0.17-5","0.17.41+really0.17-6"],"ecosystem_specific":{"binaries":[{"binary_name":"telnet-ssl","binary_version":"0.17.41+really0.17-6"},{"binary_name":"telnetd-ssl","binary_version":"0.17.41+really0.17-6"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2020/UBUNTU-CVE-2020-10188.json"}},{"package":{"name":"netkit-telnet-ssl","ecosystem":"Ubuntu:26.04:LTS","purl":"pkg:deb/ubuntu/netkit-telnet-ssl?arch=source&distro=resolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.17.41+really0.17-6","0.17.41+really0.17-7"],"ecosystem_specific":{"binaries":[{"binary_name":"telnet-ssl","binary_version":"0.17.41+really0.17-7"},{"binary_name":"telnetd-ssl","binary_version":"0.17.41+really0.17-7"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2020/UBUNTU-CVE-2020-10188.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"},{"type":"Ubuntu","score":"medium"}]}