{"id":"CVE-2019-0053","url":"https://www.cyber-defence.io/tools/cve/CVE-2019-0053","generatedAt":"2026-10-28T21:22:48.667Z","title":"Insufficient validation of environment variables in the telnet client supplied in Junos OS can lead to stack-based buffer overflows, which can be exploited to bypass veriexec restrictions on Junos OS.","description":"Insufficient validation of environment variables in the telnet client supplied in Junos OS can lead to stack-based buffer overflows, which can be exploited to bypass veriexec restrictions on Junos OS. A stack-based overflow is present in the handling of environment variables when connecting via the telnet client to remote telnet servers. This issue only affects the telnet client — accessible from the CLI or shell — in Junos OS. Inbound telnet services are not affected by this issue. This issue affects: Juniper Networks Junos OS: 12.3 versions prior to 12.3R12-S13; 12.3X48 versions prior to 12.3X48-D80; 14.1X53 versions prior to 14.1X53-D130, 14.1X53-D49; 15.1 versions prior to 15.1F6-S12, 15.1R7-S4; 15.1X49 versions prior to 15.1X49-D170; 15.1X53 versions prior to 15.1X53-D237, 15.1X53-D496, 15.1X53-D591, 15.1X53-D69; 16.1 versions prior to 16.1R3-S11, 16.1R7-S4; 16.2 versions prior to 16.2R2-S9; 17.1 versions prior to 17.1R3; 17.2 versions prior to 17.2R1-S8, 17.2R2-S7, 17.2R3-S1; 17.3 versions prior to 17.3R3-S4; 17.4 versions prior to 17.4R1-S6, 17.4R2-S3, 17.4R3; 18.1 versions prior to 18.1R2-S4, 18.1R3-S3; 18.2 versions prior to 18.2R1-S5, 18.2R2-S2, 18.2R3; 18.2X75 versions prior to 18.2X75-D40; 18.3 versions prior to 18.3R1-S3, 18.3R2; 18.4 versions prior to 18.4R1-S2, 18.4R2.","published":"2019-07-11T20:15:12.000Z","lastModified":"2026-06-17T02:07:37.000Z","status":"Modified","sourceIdentifier":"sirt@juniper.net","cvss":{"version":"3.1","score":7.8,"severity":"HIGH","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"},"cwe":["CWE-121","CWE-787"],"affected":["juniper/junos","debian/debian linux"],"epss":{"score":0.00587,"percentile":0.47854,"date":"2026-10-27","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (0.59%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"http://packetstormsecurity.com/files/153746/FreeBSD-Security-Advisory-FreeBSD-SA-19-12.telnet.html","tags":["Third Party Advisory","VDB Entry"],"source":"sirt@juniper.net"},{"url":"https://kb.juniper.net/JSA10947","tags":["Vendor Advisory"],"source":"sirt@juniper.net"},{"url":"https://lists.debian.org/debian-lts-announce/2022/11/msg00033.html","tags":["Issue Tracking","Third Party Advisory"],"source":"sirt@juniper.net"},{"url":"https://lists.debian.org/debian-lts-announce/2023/10/msg00013.html","source":"sirt@juniper.net"},{"url":"https://lists.debian.org/debian-lts-announce/2023/10/msg00013.html","source":"sirt@juniper.net"},{"url":"https://lists.debian.org/debian-lts-announce/2023/10/msg00013.html","source":"sirt@juniper.net"},{"url":"https://lists.debian.org/debian-lts-announce/2023/10/msg00013.html","source":"sirt@juniper.net"},{"url":"https://seclists.org/bugtraq/2019/Jul/45","tags":["Mailing List","Third Party Advisory"],"source":"sirt@juniper.net"},{"url":"https://security.FreeBSD.org/advisories/FreeBSD-SA-19:12.telnet.asc","tags":["Third Party Advisory"],"source":"sirt@juniper.net"},{"url":"https://www.exploit-db.com/exploits/45982","tags":["Exploit","Third Party Advisory","VDB Entry"],"source":"sirt@juniper.net"},{"url":"http://packetstormsecurity.com/files/153746/FreeBSD-Security-Advisory-FreeBSD-SA-19-12.telnet.html","tags":["Third Party Advisory","VDB Entry"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://kb.juniper.net/JSA10947","tags":["Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.debian.org/debian-lts-announce/2022/11/msg00033.html","tags":["Issue Tracking","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.debian.org/debian-lts-announce/2023/10/msg00013.html","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.debian.org/debian-lts-announce/2023/10/msg00013.html","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.debian.org/debian-lts-announce/2023/10/msg00013.html","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.debian.org/debian-lts-announce/2023/10/msg00013.html","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://seclists.org/bugtraq/2019/Jul/45","tags":["Mailing List","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://security.FreeBSD.org/advisories/FreeBSD-SA-19:12.telnet.asc","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.exploit-db.com/exploits/45982","tags":["Exploit","Third Party Advisory","VDB Entry"],"source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2019-0053","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}