{"id":"CVE-2020-1045","details":"\u003cp\u003eA security feature bypass vulnerability exists in the way Microsoft ASP.NET Core parses encoded cookie names.\u003c/p\u003e\n\u003cp\u003eThe ASP.NET Core cookie parser decodes entire cookie strings which could allow a malicious attacker to set a second cookie with the name being percent encoded.\u003c/p\u003e\n\u003cp\u003eThe security update addresses the vulnerability by fixing the way the ASP.NET Core cookie parser handles encoded names.\u003c/p\u003e","aliases":["BIT-aspnet-core-2020-1045","GHSA-hxrm-9w7p-39cc"],"modified":"2026-07-08T05:53:31.651458579Z","published":"2020-09-11T17:15:18.307Z","database_specific":{"unresolved_ranges":[{"extracted_events":[{"introduced":"32"},{"last_affected":"32"},{"introduced":"33"},{"last_affected":"33"}],"source":"CPE_STRING","vendor_product":"fedoraproject:fedora","cpes":["cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:*","cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*"]},{"extracted_events":[{"introduced":"8.0"},{"last_affected":"8.0"}],"source":"CPE_STRING","vendor_product":"redhat:enterprise_linux","cpes":["cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*"]},{"source":"CPE_STRING","vendor_product":"redhat:enterprise_linux_aus","cpes":["cpe:2.3:o:redhat:enterprise_linux_aus:8.2:*:*:*:*:*:*:*","cpe:2.3:o:redhat:enterprise_linux_aus:8.4:*:*:*:*:*:*:*","cpe:2.3:o:redhat:enterprise_linux_aus:8.6:*:*:*:*:*:*:*"],"extracted_events":[{"introduced":"8.2"},{"last_affected":"8.2"},{"introduced":"8.4"},{"last_affected":"8.4"},{"introduced":"8.6"},{"last_affected":"8.6"}]},{"source":"CPE_STRING","vendor_product":"redhat:enterprise_linux_eus","cpes":["cpe:2.3:o:redhat:enterprise_linux_eus:8.2:*:*:*:*:*:*:*","cpe:2.3:o:redhat:enterprise_linux_eus:8.4:*:*:*:*:*:*:*","cpe:2.3:o:redhat:enterprise_linux_eus:8.6:*:*:*:*:*:*:*"],"extracted_events":[{"introduced":"8.2"},{"last_affected":"8.2"},{"introduced":"8.4"},{"last_affected":"8.4"},{"introduced":"8.6"},{"last_affected":"8.6"}]},{"vendor_product":"redhat:enterprise_linux_tus","cpes":["cpe:2.3:o:redhat:enterprise_linux_tus:8.2:*:*:*:*:*:*:*","cpe:2.3:o:redhat:enterprise_linux_tus:8.4:*:*:*:*:*:*:*","cpe:2.3:o:redhat:enterprise_linux_tus:8.6:*:*:*:*:*:*:*"],"extracted_events":[{"introduced":"8.2"},{"last_affected":"8.2"},{"introduced":"8.4"},{"last_affected":"8.4"},{"introduced":"8.6"},{"last_affected":"8.6"}],"source":"CPE_STRING"}]},"references":[{"type":"WEB","url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5LN2FUVBSVPGK7AU3NMLO3YR6CGONQPB/"},{"type":"WEB","url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ASICXQXS4M7MTAF6SGQMCLCA63DLCUT3/"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2020:3699"},{"type":"ADVISORY","url":"https://github.com/dotnet/core/blob/main/release-notes/3.1/3.1.8/3.1.8.md#changes-in-318"},{"type":"ADVISORY","url":"https://security.snyk.io/vuln/SNYK-RHEL8-DOTNET-1439600"},{"type":"FIX","url":"https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-1045"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/dotnet/aspnetcore","events":[{"introduced":"00e08d8c11f4e9649492342c9c613a758efd2e4d"},{"last_affected":"adc6f4d362456fd5a4d6f35e66a10bb8b1660470"},{"introduced":"03019875e4eab279a99ba3ba5ee75fb0e4935ce6"},{"fixed":"c75b3f7a2fb9fe21fd96c93c070fdfa88a2fbe97"}],"database_specific":{"cpe":"cpe:2.3:a:microsoft:asp.net_core:*:*:*:*:*:*:*:*","extracted_events":[{"introduced":"2.1"},{"last_affected":"2.1.21"},{"introduced":"3.1"},{"fixed":"3.1.8"}],"source":"CPE_RANGE"}}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2020-1045.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:N/I:H/A:N"}]}