{"api_version":"1","generated_at":"2026-04-23T00:39:31+00:00","cve":"CVE-2018-20852","urls":{"html":"https://cve.report/CVE-2018-20852","api":"https://cve.report/api/cve/CVE-2018-20852.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2018-20852","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2018-20852"},"summary":{"title":"CVE-2018-20852","description":"http.cookiejar.DefaultPolicy.domain_return_ok in Lib/http/cookiejar.py in Python before 3.7.3 does not correctly validate the domain: it can be tricked into sending existing cookies to the wrong server. An attacker may abuse this flaw by using a server with a hostname that has another valid hostname as a suffix (e.g., pythonicexample.com to steal cookies for example.com). When a program uses http.cookiejar.DefaultPolicy and tries to do an HTTP connection to an attacker-controlled server, existing cookies can be leaked to the attacker. This affects 2.x through 2.7.16, 3.x before 3.4.10, 3.5.x before 3.5.7, 3.6.x before 3.6.9, and 3.7.x before 3.7.3.","state":"PUBLIC","assigner":"cve@mitre.org","published_at":"2019-07-13 21:15:00","updated_at":"2023-11-07 02:56:00"},"problem_types":["CWE-20"],"metrics":[],"references":[{"url":"https://lists.debian.org/debian-lts-announce/2020/07/msg00011.html","name":"[debian-lts-announce] 20200715 [SECURITY] [DLA 2280-1] python3.5 security update","refsource":"MLIST","tags":[],"title":"[SECURITY] [DLA 2280-1] python3.5 security update","mime":"text/html","httpstatus":"200","archivestatus":"200"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/K7HNVIFMETMFWWWUNTB72KYJYXCZOS5V/","name":"FEDORA-2019-0d3fcae639","refsource":"FEDORA","tags":[],"title":"[SECURITY] Fedora 31 Update: python2-docs-2.7.17-1.fc31 - package-announce - Fedora Mailing-Lists","mime":"text/html","httpstatus":"200","archivestatus":"200"},{"url":"https://lists.debian.org/debian-lts-announce/2019/08/msg00022.html","name":"[debian-lts-announce] 20190817 [SECURITY] [DLA 1889-1] python3.4 security update","refsource":"MLIST","tags":[],"title":"[SECURITY] [DLA 1889-1] python3.4 security update","mime":"text/html","httpstatus":"200","archivestatus":"200"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/COATURTCY7G67AYI6UDV5B2JZTBCKIDX/","name":"FEDORA-2019-758824a3ff","refsource":"","tags":[],"title":"[SECURITY] Fedora 29 Update: python2-docs-2.7.17-1.fc29 - package-announce - Fedora Mailing-Lists","mime":"text/html","httpstatus":"200","archivestatus":"200"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZBTGPBUABGXZ7WH7677OEM3NSP6ZEA76/","name":"FEDORA-2019-74ba24605e","refsource":"","tags":[],"title":"[SECURITY] Fedora 30 Update: python2-docs-2.7.17-1.fc30 - package-announce - Fedora Mailing-Lists","mime":"text/html","httpstatus":"200","archivestatus":"200"},{"url":"https://usn.ubuntu.com/4127-1/","name":"USN-4127-1","refsource":"UBUNTU","tags":[],"title":"USN-4127-1: Python vulnerabilities | Ubuntu security notices | Ubuntu","mime":"text/html","httpstatus":"200","archivestatus":"200"},{"url":"https://python-security.readthedocs.io/vuln/cookie-domain-check.html","name":"https://python-security.readthedocs.io/vuln/cookie-domain-check.html","refsource":"MISC","tags":["Vendor Advisory"],"title":"Maze Found\n | Read the Docs","mime":"text/html","httpstatus":"404","archivestatus":"404"},{"url":"https://security.gentoo.org/glsa/202003-26","name":"GLSA-202003-26","refsource":"GENTOO","tags":[],"title":"Python: Multiple vulnerabilities (GLSA 202003-26) — Gentoo security","mime":"text/html","httpstatus":"200","archivestatus":"200"},{"url":"http://lists.opensuse.org/opensuse-security-announce/2020-01/msg00040.html","name":"openSUSE-SU-2020:0086","refsource":"SUSE","tags":[],"title":"[security-announce] openSUSE-SU-2020:0086-1: important: Security update","mime":"text/html","httpstatus":"200","archivestatus":"200"},{"url":"http://lists.opensuse.org/opensuse-security-announce/2019-08/msg00074.html","name":"openSUSE-SU-2019:1989","refsource":"SUSE","tags":[],"title":"[security-announce] openSUSE-SU-2019:1989-1: moderate: Security update f","mime":"text/html","httpstatus":"200","archivestatus":"200"},{"url":"https://lists.debian.org/debian-lts-announce/2019/08/msg00040.html","name":"[debian-lts-announce] 20190831 [SECURITY] [DLA 1906-1] python2.7 security update","refsource":"MLIST","tags":[],"title":"[SECURITY] [DLA 1906-1] python2.7 security update","mime":"text/html","httpstatus":"200","archivestatus":"200"},{"url":"https://usn.ubuntu.com/4127-2/","name":"USN-4127-2","refsource":"UBUNTU","tags":[],"title":"USN-4127-2: Python vulnerabilities | Ubuntu security notices | Ubuntu","mime":"text/html","httpstatus":"200","archivestatus":"200"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/K7HNVIFMETMFWWWUNTB72KYJYXCZOS5V/","name":"FEDORA-2019-0d3fcae639","refsource":"","tags":[],"title":"[SECURITY] Fedora 31 Update: python2-docs-2.7.17-1.fc31 - package-announce - Fedora Mailing-Lists","mime":"text/html","httpstatus":"200","archivestatus":"200"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/ZBTGPBUABGXZ7WH7677OEM3NSP6ZEA76/","name":"FEDORA-2019-74ba24605e","refsource":"FEDORA","tags":[],"title":"[SECURITY] Fedora 30 Update: python2-docs-2.7.17-1.fc30 - package-announce - Fedora Mailing-Lists","mime":"text/html","httpstatus":"200","archivestatus":"200"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/COATURTCY7G67AYI6UDV5B2JZTBCKIDX/","name":"FEDORA-2019-758824a3ff","refsource":"FEDORA","tags":[],"title":"[SECURITY] Fedora 29 Update: python2-docs-2.7.17-1.fc29 - package-announce - Fedora Mailing-Lists","mime":"text/html","httpstatus":"200","archivestatus":"200"},{"url":"https://access.redhat.com/errata/RHSA-2019:3725","name":"RHSA-2019:3725","refsource":"REDHAT","tags":[],"title":"Red Hat Customer Portal","mime":"text/html","httpstatus":"200","archivestatus":"200"},{"url":"http://lists.opensuse.org/opensuse-security-announce/2019-08/msg00071.html","name":"openSUSE-SU-2019:1988","refsource":"SUSE","tags":[],"title":"[security-announce] openSUSE-SU-2019:1988-1: moderate: Security update f","mime":"text/html","httpstatus":"200","archivestatus":"200"},{"url":"https://www.oracle.com/security-alerts/cpuapr2020.html","name":"N/A","refsource":"N/A","tags":[],"title":"Oracle Critical Patch Update Advisory - April 2020","mime":"text/html","httpstatus":"200","archivestatus":"200"},{"url":"https://access.redhat.com/errata/RHSA-2019:3948","name":"RHSA-2019:3948","refsource":"REDHAT","tags":[],"title":"Red Hat Customer Portal","mime":"text/html","httpstatus":"200","archivestatus":"200"},{"url":"https://lists.debian.org/debian-lts-announce/2020/08/msg00034.html","name":"[debian-lts-announce] 20200822 [SECURITY] [DLA 2337-1] python2.7 security update","refsource":"MLIST","tags":[],"title":"[SECURITY] [DLA 2337-1] python2.7 security update","mime":"text/html","httpstatus":"200","archivestatus":"200"},{"url":"https://bugs.python.org/issue35121","name":"https://bugs.python.org/issue35121","refsource":"MISC","tags":["Exploit","Issue Tracking","Vendor Advisory"],"title":"Issue 35121: [CVE-2018-20852] Cookie domain check returns incorrect results - Python tracker","mime":"text/html","httpstatus":"200","archivestatus":"200"},{"url":"https://www.cve.org/CVERecord?id=CVE-2018-20852","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2018-20852","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[{"cve_year":"2018","cve_id":"20852","vulnerable":"1","versionEndIncluding":"","cpe1":"cpe","cpe2":"2.3","cpe3":"a","cpe4":"python","cpe5":"python","cpe6":"*","cpe7":"*","cpe8":"*","cpe9":"*","cpe10":"*","cpe11":"*","cpe12":"*","cpe13":"*"},{"cve_year":"2018","cve_id":"20852","vulnerable":"1","versionEndIncluding":"1","cpe1":"cpe","cpe2":"2.3","cpe3":"a","cpe4":"python","cpe5":"python","cpe6":"*","cpe7":"*","cpe8":"*","cpe9":"*","cpe10":"*","cpe11":"*","cpe12":"*","cpe13":"*"},{"cve_year":"2018","cve_id":"20852","vulnerable":"1","versionEndIncluding":"2.7.16","cpe1":"cpe","cpe2":"2.3","cpe3":"a","cpe4":"python","cpe5":"python","cpe6":"*","cpe7":"*","cpe8":"*","cpe9":"*","cpe10":"*","cpe11":"*","cpe12":"*","cpe13":"*"}],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[{"cve":"CVE-2018-20852","qid":"159655","title":"Oracle Enterprise Linux Security Update for python27:2.7 (ELSA-2020-1605)"},{"cve":"CVE-2018-20852","qid":"377436","title":"Alibaba Cloud Linux Security Update for python (ALINUX2-SA-2020:0081)"},{"cve":"CVE-2018-20852","qid":"377490","title":"Alibaba Cloud Linux Security Update for python3 (ALINUX2-SA-2020:0073)"},{"cve":"CVE-2018-20852","qid":"671062","title":"EulerOS Security Update for python (EulerOS-SA-2019-2442)"},{"cve":"CVE-2018-20852","qid":"940120","title":"AlmaLinux Security Update for python27:2.7 (ALSA-2020:1605)"}]},"source_records":{"cve_program":{"CVE_data_meta":{"ASSIGNER":"cve@mitre.org","ID":"CVE-2018-20852","STATE":"PUBLIC"},"affects":{"vendor":{"vendor_data":[{"product":{"product_data":[{"product_name":"n/a","version":{"version_data":[{"version_value":"n/a"}]}}]},"vendor_name":"n/a"}]}},"data_format":"MITRE","data_type":"CVE","data_version":"4.0","description":{"description_data":[{"lang":"eng","value":"http.cookiejar.DefaultPolicy.domain_return_ok in Lib/http/cookiejar.py in Python before 3.7.3 does not correctly validate the domain: it can be tricked into sending existing cookies to the wrong server. An attacker may abuse this flaw by using a server with a hostname that has another valid hostname as a suffix (e.g., pythonicexample.com to steal cookies for example.com). When a program uses http.cookiejar.DefaultPolicy and tries to do an HTTP connection to an attacker-controlled server, existing cookies can be leaked to the attacker. This affects 2.x through 2.7.16, 3.x before 3.4.10, 3.5.x before 3.5.7, 3.6.x before 3.6.9, and 3.7.x before 3.7.3."}]},"problemtype":{"problemtype_data":[{"description":[{"lang":"eng","value":"n/a"}]}]},"references":{"reference_data":[{"url":"https://bugs.python.org/issue35121","refsource":"MISC","name":"https://bugs.python.org/issue35121"},{"url":"https://python-security.readthedocs.io/vuln/cookie-domain-check.html","refsource":"MISC","name":"https://python-security.readthedocs.io/vuln/cookie-domain-check.html"},{"refsource":"MLIST","name":"[debian-lts-announce] 20190817 [SECURITY] [DLA 1889-1] python3.4 security update","url":"https://lists.debian.org/debian-lts-announce/2019/08/msg00022.html"},{"refsource":"SUSE","name":"openSUSE-SU-2019:1988","url":"http://lists.opensuse.org/opensuse-security-announce/2019-08/msg00071.html"},{"refsource":"SUSE","name":"openSUSE-SU-2019:1989","url":"http://lists.opensuse.org/opensuse-security-announce/2019-08/msg00074.html"},{"refsource":"MLIST","name":"[debian-lts-announce] 20190831 [SECURITY] [DLA 1906-1] python2.7 security update","url":"https://lists.debian.org/debian-lts-announce/2019/08/msg00040.html"},{"refsource":"UBUNTU","name":"USN-4127-2","url":"https://usn.ubuntu.com/4127-2/"},{"refsource":"UBUNTU","name":"USN-4127-1","url":"https://usn.ubuntu.com/4127-1/"},{"refsource":"REDHAT","name":"RHSA-2019:3725","url":"https://access.redhat.com/errata/RHSA-2019:3725"},{"refsource":"FEDORA","name":"FEDORA-2019-0d3fcae639","url":"https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/K7HNVIFMETMFWWWUNTB72KYJYXCZOS5V/"},{"refsource":"FEDORA","name":"FEDORA-2019-74ba24605e","url":"https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/ZBTGPBUABGXZ7WH7677OEM3NSP6ZEA76/"},{"refsource":"FEDORA","name":"FEDORA-2019-758824a3ff","url":"https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/COATURTCY7G67AYI6UDV5B2JZTBCKIDX/"},{"refsource":"REDHAT","name":"RHSA-2019:3948","url":"https://access.redhat.com/errata/RHSA-2019:3948"},{"refsource":"SUSE","name":"openSUSE-SU-2020:0086","url":"http://lists.opensuse.org/opensuse-security-announce/2020-01/msg00040.html"},{"refsource":"GENTOO","name":"GLSA-202003-26","url":"https://security.gentoo.org/glsa/202003-26"},{"url":"https://www.oracle.com/security-alerts/cpuapr2020.html","refsource":"MISC","name":"https://www.oracle.com/security-alerts/cpuapr2020.html"},{"refsource":"MLIST","name":"[debian-lts-announce] 20200715 [SECURITY] [DLA 2280-1] python3.5 security update","url":"https://lists.debian.org/debian-lts-announce/2020/07/msg00011.html"},{"refsource":"MLIST","name":"[debian-lts-announce] 20200822 [SECURITY] [DLA 2337-1] python2.7 security update","url":"https://lists.debian.org/debian-lts-announce/2020/08/msg00034.html"}]}},"nvd":{"publishedDate":"2019-07-13 21:15:00","lastModifiedDate":"2023-11-07 02:56:00","problem_types":["CWE-20"],"metrics":{"baseMetricV3":{"cvssV3":{"version":"3.0","vectorString":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"LOW","integrityImpact":"NONE","availabilityImpact":"NONE","baseScore":5.3,"baseSeverity":"MEDIUM"},"exploitabilityScore":3.9,"impactScore":1.4},"baseMetricV2":{"cvssV2":{"version":"2.0","vectorString":"AV:N/AC:L/Au:N/C:P/I:N/A:N","accessVector":"NETWORK","accessComplexity":"LOW","authentication":"NONE","confidentialityImpact":"PARTIAL","integrityImpact":"NONE","availabilityImpact":"NONE","baseScore":5},"severity":"MEDIUM","exploitabilityScore":10,"impactScore":2.9,"acInsufInfo":false,"obtainAllPrivilege":false,"obtainUserPrivilege":false,"obtainOtherPrivilege":false,"userInteractionRequired":false}},"configurations":{"CVE_data_version":"4.0","nodes":[{"operator":"OR","children":[],"cpe_match":[{"vulnerable":true,"cpe23Uri":"cpe:2.3:a:python:python:*:*:*:*:*:*:*:*","versionStartIncluding":"2.0","versionEndIncluding":"2.7.16","cpe_name":[]},{"vulnerable":true,"cpe23Uri":"cpe:2.3:a:python:python:*:*:*:*:*:*:*:*","versionStartIncluding":"3.7.0","versionEndExcluding":"3.7.3","cpe_name":[]},{"vulnerable":true,"cpe23Uri":"cpe:2.3:a:python:python:*:*:*:*:*:*:*:*","versionStartIncluding":"3.6.0","versionEndExcluding":"3.6.9","cpe_name":[]},{"vulnerable":true,"cpe23Uri":"cpe:2.3:a:python:python:*:*:*:*:*:*:*:*","versionStartIncluding":"3.5.0","versionEndExcluding":"3.5.7","cpe_name":[]},{"vulnerable":true,"cpe23Uri":"cpe:2.3:a:python:python:*:*:*:*:*:*:*:*","versionStartIncluding":"3.0.0","versionEndExcluding":"3.4.10","cpe_name":[]}]}]}},"legacy_mitre":{"record":{"CveYear":"2018","CveId":"20852","Ordinal":"151939","Title":"CVE-2018-20852","CVE":"CVE-2018-20852","Year":"2018"},"notes":[{"CveYear":"2018","CveId":"20852","Ordinal":"1","NoteData":"http.cookiejar.DefaultPolicy.domain_return_ok in Lib/http/cookiejar.py in Python before 3.7.3 does not correctly validate the domain: it can be tricked into sending existing cookies to the wrong server. An attacker may abuse this flaw by using a server with a hostname that has another valid hostname as a suffix (e.g., pythonicexample.com to steal cookies for example.com). When a program uses http.cookiejar.DefaultPolicy and tries to do an HTTP connection to an attacker-controlled server, existing cookies can be leaked to the attacker. This affects 2.x through 2.7.16, 3.x before 3.4.10, 3.5.x before 3.5.7, 3.6.x before 3.6.9, and 3.7.x before 3.7.3.","Type":"Description","Title":null},{"CveYear":"2018","CveId":"20852","Ordinal":"2","NoteData":"2019-07-13","Type":"Other","Title":"Published"},{"CveYear":"2018","CveId":"20852","Ordinal":"3","NoteData":"2020-08-22","Type":"Other","Title":"Modified"}]}}}