{"id":"CVE-2019-9636","title":"Python 2.7.x through 2.7.16 and 3.x through 3.7.2 is affected by: Improper Handling of Unicode Encoding (with an incorrect netloc) during NFKC normalization","summary":"Python 2.7.x through 2.7.16 and 3.x through 3.7.2 is affected by: Improper Handling of Unicode Encoding (with an incorrect netloc) during NFKC normalization. The impact is: Information disclosure (credentials, cookies, etc. that are cach…","severity":"critical","cvss":9.8,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","cwe":["CWE-173"],"vendor":"python","product":"python","affected":["python >= 2.7.0, < 2.7.17","python >= 3.0.0, < 3.4.10","python >= 3.5.0, < 3.5.7","python >= 3.6.0, < 3.6.9","python >= 3.7.0, < 3.7.3","fedora = 28","fedora = 29","fedora = 30","fedora = 31","leap = 15.0","leap = 15.1","leap = 42.3","debian_linux = 8.0","debian_linux = 9.0","ubuntu_linux = 12.04","ubuntu_linux = 14.04","ubuntu_linux = 16.04","ubuntu_linux = 18.04","ubuntu_linux = 19.04","openshift_container_platform = 3.11","enterprise_linux = 7.5","enterprise_linux = 8.0","enterprise_linux_desktop = 6.0","enterprise_linux_eus = 7.5","enterprise_linux_eus = 8.1","enterprise_linux_eus = 8.2","enterprise_linux_eus = 8.4","enterprise_linux_eus = 8.6","enterprise_linux_server = 6.0","enterprise_linux_server_aus = 7.4","enterprise_linux_server_aus = 8.2","enterprise_linux_server_aus = 8.4","enterprise_linux_server_eus = 5.6","enterprise_linux_server_tus = 7.4","enterprise_linux_server_tus = 8.2","enterprise_linux_server_tus = 8.4","enterprise_linux_server_tus = 8.6","enterprise_linux_workstation = 6.0","virtualization = 4.0","sun_zfs_storage_appliance_kit = 8.8.6"],"patched":["python 3.7.3"],"published":"2019-03-08","updated":"2026-10-07","sourceUpdated":"2026-10-07T19:17:14.490","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2019-9636","references":[{"url":"http://lists.opensuse.org/opensuse-security-announce/2019-04/msg00092.html","label":"cve@mitre.org"},{"url":"http://lists.opensuse.org/opensuse-security-announce/2019-04/msg00097.html","label":"cve@mitre.org"},{"url":"http://lists.opensuse.org/opensuse-security-announce/2019-05/msg00024.html","label":"cve@mitre.org"},{"url":"http://lists.opensuse.org/opensuse-security-announce/2019-06/msg00050.html","label":"cve@mitre.org"},{"url":"http://lists.opensuse.org/opensuse-security-announce/2019-08/msg00042.html","label":"cve@mitre.org"},{"url":"http://lists.opensuse.org/opensuse-security-announce/2020-01/msg00040.html","label":"cve@mitre.org"},{"url":"http://www.securityfocus.com/bid/107400","label":"cve@mitre.org"},{"url":"https://access.redhat.com/errata/RHBA-2019:0763","label":"cve@mitre.org"},{"url":"https://access.redhat.com/errata/RHBA-2019:0764","label":"cve@mitre.org"},{"url":"https://access.redhat.com/errata/RHBA-2019:0959","label":"cve@mitre.org"},{"url":"https://access.redhat.com/errata/RHSA-2019:0710","label":"cve@mitre.org"},{"url":"https://access.redhat.com/errata/RHSA-2019:0765","label":"cve@mitre.org"},{"url":"https://access.redhat.com/errata/RHSA-2019:0806","label":"cve@mitre.org"},{"url":"https://access.redhat.com/errata/RHSA-2019:0902","label":"cve@mitre.org"},{"url":"https://access.redhat.com/errata/RHSA-2019:0981","label":"cve@mitre.org"},{"url":"https://access.redhat.com/errata/RHSA-2019:0997","label":"cve@mitre.org"},{"url":"https://access.redhat.com/errata/RHSA-2019:1467","label":"cve@mitre.org"},{"url":"https://access.redhat.com/errata/RHSA-2019:2980","label":"cve@mitre.org"},{"url":"https://access.redhat.com/errata/RHSA-2019:3170","label":"cve@mitre.org"},{"url":"https://bugs.python.org/issue36216","label":"cve@mitre.org"},{"url":"https://github.com/python/cpython/pull/12201","label":"cve@mitre.org"},{"url":"https://lists.debian.org/debian-lts-announce/2019/06/msg00022.html","label":"cve@mitre.org"},{"url":"https://lists.debian.org/debian-lts-announce/2019/06/msg00023.html","label":"cve@mitre.org"},{"url":"https://lists.debian.org/debian-lts-announce/2020/07/msg00011.html","label":"cve@mitre.org"},{"url":"https://lists.debian.org/debian-lts-announce/2020/08/msg00034.html","label":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/2ORNTF62QPLMJXIQ7KTZQ2776LMIXEKL/","label":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/44TS66GJMO5H3RLMVZEBGEFTB6O2LJJU/","label":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/46PVWY5LFP4BRPG3BVQ5QEEFYBVEXHCK/","label":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4X3HW5JRZ7GCPSR7UHJOLD7AWLTQCDVR/","label":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/AEZ5IQT7OF7Q2NCGIVABOWYGKO7YU3NJ/","label":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CFBAAGM27H73OLYBUA2IAZFSUN6KGLME/","label":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/D3LXPABKVLFYUHRYJPM3CSS5MS6FXKS7/","label":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/E2HP37NUVLQSBW3J735A2DQDOZ4ZGBLY/","label":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ER6LONC2B2WYIO56GBQUDU6QTWZDPUNQ/","label":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/HQEQLXLOCR3SNM3AA5RRYJFQ5AZBYJ4L/","label":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ICBEGRHIPHWPG2VGYS6R4EVKVUUF4AQW/","label":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/IFAXBEY2TGOBDRKTR556JBXBVFSAKD6I/","label":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/JCPGLTTOBB3QEARDX4JOYURP6ELNNA2V/","label":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/JMWSKTNOHSUOT3L25QFJAVCFYZX46FYK/","label":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/JSKPGPZQNTAULHW4UH63KGOOUIDE4RRB/","label":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40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Overview\n\nPython 2.7.x through 2.7.16 and 3.x through 3.7.2 is affected by: Improper Handling of Unicode Encoding (with an incorrect netloc) during NFKC normalization. The impact is: Information disclosure (credentials, cookies, etc. that are cached against a given hostname). The components are: urllib.parse.urlsplit, urllib.parse.urlparse. The attack vector is: A specially crafted URL could be incorrectly parsed to locate cookies or authentication data and send that information to a different host than when parsed correctly. This is fixed in: v2.7.17, v2.7.17rc1, v2.7.18, v2.7.18rc1; v3.5.10, v3.5.10rc1, v3.5.7, v3.5.8, v3.5.8rc1, v3.5.8rc2, v3.5.9; v3.6.10, v3.6.10rc1, v3.6.11, v3.6.11rc1, v3.6.12, v3.6.9, v3.6.9rc1; v3.7.3, v3.7.3rc1, v3.7.4, v3.7.4rc1, v3.7.4rc2, v3.7.5, v3.7.5rc1, v3.7.6, v3.7.6rc1, v3.7.7, v3.7.7rc1, v3.7.8, v3.7.8rc1, v3.7.9.\n\n## Affected\n\n- `python >= 2.7.0, < 2.7.17`\n- `python >= 3.0.0, < 3.4.10`\n- `python >= 3.5.0, < 3.5.7`\n- `python >= 3.6.0, < 3.6.9`\n- `python >= 3.7.0, < 3.7.3`\n- `fedora = 28`\n- `fedora = 29`\n- `fedora = 30`\n- `fedora = 31`\n- `leap = 15.0`\n- `leap = 15.1`\n- `leap = 42.3`\n- `debian_linux = 8.0`\n- `debian_linux = 9.0`\n- `ubuntu_linux = 12.04`\n- `ubuntu_linux = 14.04`\n- `ubuntu_linux = 16.04`\n- `ubuntu_linux = 18.04`\n- `ubuntu_linux = 19.04`\n- `openshift_container_platform = 3.11`\n- `enterprise_linux = 7.5`\n- `enterprise_linux = 8.0`\n- `enterprise_linux_desktop = 6.0`\n- `enterprise_linux_eus = 7.5`\n- `enterprise_linux_eus = 8.1`\n- `enterprise_linux_eus = 8.2`\n- `enterprise_linux_eus = 8.4`\n- `enterprise_linux_eus = 8.6`\n- `enterprise_linux_server = 6.0`\n- `enterprise_linux_server_aus = 7.4`\n- `enterprise_linux_server_aus = 8.2`\n- `enterprise_linux_server_aus = 8.4`\n- `enterprise_linux_server_eus = 5.6`\n- `enterprise_linux_server_tus = 7.4`\n- `enterprise_linux_server_tus = 8.2`\n- `enterprise_linux_server_tus = 8.4`\n- `enterprise_linux_server_tus = 8.6`\n- `enterprise_linux_workstation = 6.0`\n- `virtualization = 4.0`\n- `sun_zfs_storage_appliance_kit = 8.8.6`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `python 3.7.3`","depth":"midnight","depthScore":56,"depthScoreParts":{"impact":53.9,"likelihood":1.8,"exploitation":0,"ransomware":0},"changes":[{"seq":217667,"id":"CVE-2019-9636","ts":1791402292249,"field":"cvss","old":"5.3","new":"9.8"},{"seq":217666,"id":"CVE-2019-9636","ts":1791402292249,"field":"severity","old":"medium","new":"critical"}]}