{"id":"CVE-2020-15136","aliases":["AZL-6393","DEBIAN-CVE-2020-15136","EUVD-2024-0452","GHSA-wr2v-9rpq-c35q","RHSA-2021:0916","UBUNTU-CVE-2020-15136"],"status":"published","title":"Improper authentication in etcd","description":"In ectd before versions 3.4.10 and 3.3.23, gateway TLS authentication is only applied to endpoints detected in DNS SRV records. When starting a gateway, TLS authentication will only be attempted on endpoints identified in DNS SRV records for a given domain, which occurs in the discoverEndpoints function. No authentication is performed against endpoints provided in the --endpoints flag. This has been fixed in versions 3.4.10 and 3.3.23 with improved documentation and deprecation of the functionality.","severity":{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-09","score":0.0165,"percentile":0.76683,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-287","CWE-306"],"published":"2020-08-06T22:45:14Z","modified":"2026-10-26T12:00:23Z","fixes":[{"ecosystem":"Go","package":"go.etcd.io/etcd","fixed_in":["3.4.10","3.3.23"],"sources":["ghsa","osv"]},{"ecosystem":"Azure Linux:2","package":"etcd","fixed_in":["3.5.0-3"],"sources":["osv"]},{"ecosystem":"Debian:12","package":"etcd","fixed_in":["3.3.25+dfsg-5"],"sources":["osv"]},{"ecosystem":"Debian:13","package":"etcd","fixed_in":["3.3.25+dfsg-5"],"sources":["osv"]},{"ecosystem":"Debian:14","package":"etcd","fixed_in":["3.3.25+dfsg-5"],"sources":["osv"]}],"affected":[{"source":"ghsa","ecosystem":"Go","package":"go.etcd.io/etcd","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"3.4.0-rc.0"},{"last_affected":"3.4.9"},{"fixed":"3.4.10"}]}]},{"source":"ghsa","ecosystem":"Go","package":"go.etcd.io/etcd","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.3.23"}]}]},{"source":"osv","ecosystem":"Azure Linux:2","package":"etcd","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.5.0-3"}]}]},{"source":"osv","ecosystem":"Debian:12","package":"etcd","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.3.25+dfsg-5"}]}]},{"source":"osv","ecosystem":"Debian:13","package":"etcd","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.3.25+dfsg-5"}]}]},{"source":"osv","ecosystem":"Debian:14","package":"etcd","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.3.25+dfsg-5"}]}]},{"source":"osv","ecosystem":"Go","package":"go.etcd.io/etcd","ranges":[{"type":"SEMVER","events":[{"introduced":"3.4.0-rc.0"},{"fixed":"3.4.10"}]}]},{"source":"osv","ecosystem":"Go","package":"go.etcd.io/etcd","ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"3.3.23"}]}]},{"source":"osv","ecosystem":"Red Hat:openstack:16.1::el8","package":"etcd","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0:3.3.23-1.el8ost"}]}],"bundled":6},{"source":"osv","ecosystem":"Red Hat:openstack:16.1::el8","package":"etcd-debuginfo","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0:3.3.23-1.el8ost"}]}],"bundled":6},{"source":"osv","ecosystem":"Red Hat:openstack:16.1::el8","package":"etcd-debugsource","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0:3.3.23-1.el8ost"}]}],"bundled":6},{"source":"osv","ecosystem":"Ubuntu:16.04:LTS","package":"etcd","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.2.0+dfsg-2","2.2.1+dfsg-1","2.2.2+dfsg-1","2.2.2+dfsg-2","2.2.3+dfsg-1","2.2.5+dfsg-1","2.2.5+dfsg-1ubuntu1"]},{"source":"osv","ecosystem":"Ubuntu:Pro:18.04:LTS","package":"etcd","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.1.0-1","3.2.9+dfsg-2","3.2.9+dfsg-3","3.2.17+dfsg-1","3.2.17+dfsg-1ubuntu0.1~esm1","3.2.17+dfsg-1ubuntu0.1","3.2.17+dfsg-1ubuntu0.1+esm1","3.2.17+dfsg-1ubuntu0.1+esm2"]},{"source":"osv","ecosystem":"Ubuntu:Pro:20.04:LTS","package":"etcd","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.2.26+dfsg-3","3.2.26+dfsg-4","3.2.26+dfsg-6","3.2.26+dfsg-6ubuntu0.1","3.2.26+dfsg-6ubuntu0.2","3.2.26+dfsg-6ubuntu0.2+esm1"]},{"source":"osv","ecosystem":"Ubuntu:Pro:22.04:LTS","package":"etcd","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.3.25+dfsg-6","3.3.25+dfsg-7","3.3.25+dfsg-7ubuntu0.22.04.1","3.3.25+dfsg-7ubuntu0.22.04.1+esm1","3.3.25+dfsg-7ubuntu0.22.04.2","3.3.25+dfsg-7ubuntu0.22.04.2+esm1","3.3.25+dfsg-7ubuntu0.22.04.2+esm2","3.3.25+dfsg-7ubuntu0.22.04.2+esm3"]},{"source":"osv","ecosystem":"Ubuntu:Pro:24.04:LTS","package":"etcd","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.4.23-4ubuntu2","3.4.30-1","3.4.30-1build1","3.4.30-1ubuntu0.24.04.1","3.4.30-1ubuntu0.24.04.2","3.4.30-1ubuntu0.24.04.2+esm1","3.4.30-1ubuntu0.24.04.3","3.4.30-1ubuntu0.24.04.3+esm1","3.4.30-1ubuntu0.24.04.3+esm2"]},{"source":"osv","ecosystem":"Ubuntu:25.10","package":"etcd","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.5.16-4"]},{"source":"osv","ecosystem":"Ubuntu:26.10","package":"etcd","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.5.16-10","3.5.30-2"]},{"source":"osv","ecosystem":"Ubuntu:Pro:26.04:LTS","package":"etcd","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.5.16-4","3.5.16-10","3.5.16-10ubuntu0.26.04.1~esm1"]}],"products":[{"vendor":"etcd-io","product":"etcd"},{"vendor":"fedoraproject","product":"fedora"},{"vendor":"redhat","product":"etcd"}],"references":[{"url":"https://github.com/etcd-io/etcd/security/advisories/GHSA-wr2v-9rpq-c35q","tags":["x_refsource_CONFIRM","x_transferred","Third Party Advisory","advisory","web","article","report"]},{"url":"https://github.com/etcd-io/etcd/blob/master/Documentation/op-guide/gateway.md","tags":["x_refsource_MISC","x_transferred","Broken Link","web","report"]},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/L6B6R43Y7M3DCHWK3L3UVGE2K6WWECMP/","tags":["vendor-advisory","x_refsource_FEDORA","x_transferred","web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2020-15136","tags":["web","advisory"]},{"url":"https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/L6B6R43Y7M3DCHWK3L3UVGE2K6WWECMP/"},{"url":"https://github.com/advisories/GHSA-wr2v-9rpq-c35q"},{"url":"https://security-tracker.debian.org/tracker/CVE-2020-15136","tags":["advisory"]},{"url":"https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/L6B6R43Y7M3DCHWK3L3UVGE2K6WWECMP","tags":["web"]},{"url":"https://access.redhat.com/errata/RHSA-2021:0916","tags":["advisory"]},{"url":"https://access.redhat.com/security/updates/classification/#moderate","tags":["article"]},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=1868870","tags":["report"]},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=1868872","tags":["report"]},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=1868874","tags":["report"]},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=1868878","tags":["report"]},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=1868880","tags":["report"]},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=1868883","tags":["report"]},{"url":"https://security.access.redhat.com/data/csaf/v2/advisories/2021/rhsa-2021_0916.json","tags":["advisory"]},{"url":"https://access.redhat.com/security/cve/CVE-2020-15106","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2020-15106","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2020-15106","tags":["advisory"]},{"url":"https://github.com/etcd-io/etcd/security/advisories/GHSA-p4g4-wgrh-qrg2","tags":["article"]},{"url":"https://access.redhat.com/security/cve/CVE-2020-15112","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2020-15112","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2020-15112","tags":["advisory"]},{"url":"https://github.com/etcd-io/etcd/security/advisories/GHSA-m332-53r6-2w93","tags":["article"]},{"url":"https://access.redhat.com/security/cve/CVE-2020-15113","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2020-15113","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2020-15113","tags":["advisory"]},{"url":"https://github.com/etcd-io/etcd/security/advisories/GHSA-chh6-ppwq-jh92","tags":["article"]},{"url":"https://access.redhat.com/security/cve/CVE-2020-15114","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2020-15114","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2020-15114","tags":["advisory"]},{"url":"https://github.com/etcd-io/etcd/security/advisories/GHSA-2xhq-gv6c-p224","tags":["article"]},{"url":"https://access.redhat.com/security/cve/CVE-2020-15115","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2020-15115","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2020-15115","tags":["advisory"]},{"url":"https://github.com/etcd-io/etcd/security/advisories/GHSA-4993-m7g5-r9hh","tags":["article"]},{"url":"https://access.redhat.com/security/cve/CVE-2020-15136","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2020-15136","tags":["advisory","report"]},{"url":"https://ubuntu.com/security/CVE-2020-15136","tags":["report"]}],"sources":{"cve":[{"id":"CVE-2020-15136","title":"Improper authentication in etcd","description":"In ectd before versions 3.4.10 and 3.3.23, gateway TLS authentication is only applied to endpoints detected in DNS SRV records. When starting a gateway, TLS authentication will only be attempted on endpoints identified in DNS SRV records for a given domain, which occurs in the discoverEndpoints function. No authentication is performed against endpoints provided in the --endpoints flag. This has been fixed in versions 3.4.10 and 3.3.23 with improved documentation and deprecation of the functionality.","status":"published","published":"2020-08-06T22:45:14Z","modified":"2024-08-04T13:08:21.951Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N","level":"medium","assessor":"cna"}],"cwes":["CWE-287"],"updated_at":"2026-11-02T14:35:50.228781Z"}],"euvd":[{"id":"EUVD-2024-0452","description":"In ectd before versions 3.4.10 and 3.3.23, gateway TLS authentication is only applied to endpoints detected in DNS SRV records. When starting a gateway, TLS authentication will only be attempted on endpoints identified in DNS SRV records for a given domain, which occurs in the discoverEndpoints function. No authentication is performed against endpoints provided in the --endpoints flag. This has been fixed in versions 3.4.10 and 3.3.23 with improved documentation and deprecation of the functionality.","status":"published","published":"2020-08-06T22:45:14Z","modified":"2024-08-04T13:08:21Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N","level":"medium"}],"updated_at":"2026-11-03T03:07:33.100327Z"}],"ghsa":[{"id":"GHSA-wr2v-9rpq-c35q","title":"Etcd Gateway TLS authentication only applies to endpoints detected in DNS SRV records","description":"### Vulnerability type\nCryptography\n\n### Workarounds\nRefer to the [gateway documentation](https://github.com/etcd-io/etcd/blob/master/Documentation/op-guide/gateway.md). The vulnerability was spotted due to unclear documentation of how the gateway handles endpoints validation.\n\n### Detail\nWhen starting a gateway, TLS authentication will only be attempted on endpoints identified in DNS SRV records for a given domain, which occurs in the discoverEndpoints function. No authentication is performed against endpoints provided in the --endpoints flag. The auditors has noted that appropriate documentation of this validation functionality plus deprecation of this misleading functionality is an acceptable path forward.\n \n### References\nFind out more on this vulnerability in the [security audit report](https://github.com/etcd-io/etcd/blob/master/security/SECURITY_AUDIT.pdf)\n\n### For more information\nIf you have any questions or comments about this advisory:\n* Contact the [etcd security committee](https://github.com/etcd-io/etcd/blob/master/security/security-release-process.md#product-security-committee-psc)","status":"published","published":"2024-01-31T00:21:56Z","modified":"2024-01-31T00:22:00Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N","level":"medium"}],"cwes":["CWE-287","CWE-306"],"updated_at":"2026-11-02T14:37:34.405364Z"}],"nvd":[{"id":"CVE-2020-15136","description":"In ectd before versions 3.4.10 and 3.3.23, gateway TLS authentication is only applied to endpoints detected in DNS SRV records. When starting a gateway, TLS authentication will only be attempted on endpoints identified in DNS SRV records for a given domain, which occurs in the discoverEndpoints function. No authentication is performed against endpoints provided in the --endpoints flag. This has been fixed in versions 3.4.10 and 3.3.23 with improved documentation and deprecation of the functionality.","status":"published","published":"2020-08-06T23:15:11.577Z","modified":"2026-06-17T02:56:07.333Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N","level":"medium","assessor":"secondary"},{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N","level":"medium","assessor":"primary"},{"version":"2.0","score":5.8,"vector":"AV:N/AC:M/Au:N/C:P/I:P/A:N","level":"medium","assessor":"primary"}],"cwes":["CWE-287","CWE-306"],"updated_at":"2026-11-02T14:06:10.994748Z"}],"osv":[{"id":"AZL-6393","title":"CVE-2020-15136 affecting package etcd for versions less than 3.5.0-3","description":"In ectd before versions 3.4.10 and 3.3.23, gateway TLS authentication is only applied to endpoints detected in DNS SRV records. When starting a gateway, TLS authentication will only be attempted on endpoints identified in DNS SRV records for a given domain, which occurs in the discoverEndpoints function. No authentication is performed against endpoints provided in the --endpoints flag. This has been fixed in versions 3.4.10 and 3.3.23 with improved documentation and deprecation of the functionality.","status":"published","published":"2020-08-06T23:15:11Z","modified":"2026-04-21T04:32:15.813354Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N","level":"medium"}],"updated_at":"2026-11-02T15:28:07.805289Z"},{"id":"CVE-2020-15136","description":"In ectd before versions 3.4.10 and 3.3.23, gateway TLS authentication is only applied to endpoints detected in DNS SRV records. When starting a gateway, TLS authentication will only be attempted on endpoints identified in DNS SRV records for a given domain, which occurs in the discoverEndpoints function. No authentication is performed against endpoints provided in the --endpoints flag. This has been fixed in versions 3.4.10 and 3.3.23 with improved documentation and deprecation of the functionality.","status":"published","published":"2020-08-06T23:15:11.577Z","modified":"2026-10-20T10:51:52.064864448Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N","level":"medium"}],"updated_at":"2026-11-02T15:44:14.418339Z"},{"id":"DEBIAN-CVE-2020-15136","description":"In ectd before versions 3.4.10 and 3.3.23, gateway TLS authentication is only applied to endpoints detected in DNS SRV records. When starting a gateway, TLS authentication will only be attempted on endpoints identified in DNS SRV records for a given domain, which occurs in the discoverEndpoints function. No authentication is performed against endpoints provided in the --endpoints flag. This has been fixed in versions 3.4.10 and 3.3.23 with improved documentation and deprecation of the functionality.","status":"published","published":"2020-08-06T23:15:11.577Z","modified":"2026-10-26T12:00:23.143422369Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N","level":"medium"}],"updated_at":"2026-11-02T15:45:33.384087Z"},{"id":"GHSA-wr2v-9rpq-c35q","title":"Etcd Gateway TLS authentication only applies to endpoints detected in DNS SRV records","description":"### Vulnerability type\nCryptography\n\n### Workarounds\nRefer to the [gateway documentation](https://github.com/etcd-io/etcd/blob/master/Documentation/op-guide/gateway.md). The vulnerability was spotted due to unclear documentation of how the gateway handles endpoints validation.\n\n### Detail\nWhen starting a gateway, TLS authentication will only be attempted on endpoints identified in DNS SRV records for a given domain, which occurs in the discoverEndpoints function. No authentication is performed against endpoints provided in the --endpoints flag. The auditors has noted that appropriate documentation of this validation functionality plus deprecation of this misleading functionality is an acceptable path forward.\n \n### References\nFind out more on this vulnerability in the [security audit report](https://github.com/etcd-io/etcd/blob/master/security/SECURITY_AUDIT.pdf)\n\n### For more information\nIf you have any questions or comments about this advisory:\n* Contact the [etcd security committee](https://github.com/etcd-io/etcd/blob/master/security/security-release-process.md#product-security-committee-psc)","status":"published","published":"2024-01-31T00:21:56Z","modified":"2026-09-10T03:50:09.551282141Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N","level":"medium"}],"cwes":["CWE-287","CWE-306"],"updated_at":"2026-11-02T15:46:59.131095Z"},{"id":"RHSA-2021:0916","title":"Red Hat Security Advisory: Red Hat OpenStack Platform 16.1.4 (etcd) security update","status":"published","published":"2024-09-18T04:28:58Z","modified":"2026-06-27T10:13:05Z","cvss":[{"version":"3.1","score":7.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H","level":"high"}],"updated_at":"2026-11-02T15:53:08.071325Z"},{"id":"UBUNTU-CVE-2020-15136","description":"In ectd before versions 3.4.10 and 3.3.23, gateway TLS authentication is only applied to endpoints detected in DNS SRV records. When starting a gateway, TLS authentication will only be attempted on endpoints identified in DNS SRV records for a given domain, which occurs in the discoverEndpoints function. No authentication is performed against endpoints provided in the --endpoints flag. This has been fixed in versions 3.4.10 and 3.3.23 with improved documentation and deprecation of the functionality.","status":"published","published":"2020-08-06T23:15:00Z","modified":"2026-10-17T12:56:11.300205604Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N","level":"medium"},{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N","level":"medium"}],"updated_at":"2026-11-02T15:54:23.344108Z"}]}}