{"id":"CVE-2021-28861","title":"Python 3.x through 3.10 has an open redirection vulnerability in lib/http/server.py due to no protection against multiple (/) at the beginning of URI path which may leads to information disclosure","summary":"Python 3.x through 3.10 has an open redirection vulnerability in lib/http/server.py due to no protection against multiple (/) at the beginning of URI path which may leads to information disclosure. NOTE: this is disputed by a third party…","severity":"high","cvss":7.4,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:N/A:N","cwe":["CWE-601","CWE-601"],"vendor":"python","product":"python","affected":["python >= 3.0.0, < 3.7.14","python >= 3.8.0, < 3.8.14","python >= 3.9.0, < 3.9.14","python >= 3.10.0, < 3.10.6","python = 3.11.0","fedora = 35","fedora = 36","fedora = 37"],"patched":["python 3.10.6"],"published":"2022-08-23","updated":"2026-10-14","sourceUpdated":"2026-10-14T12:17:11.267","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2021-28861","references":[{"url":"https://bugs.python.org/issue43223","label":"cve@mitre.org"},{"url":"https://github.com/python/cpython/pull/24848","label":"cve@mitre.org"},{"url":"https://github.com/python/cpython/pull/93879","label":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/2TRINJE3INWDVIHIABW4L2NP3RUSK7BJ/","label":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5LTSPFIULY2GZJN3QYNFVM4JSU6H4D6J/","label":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5OABQ5CMPQETJLFHROAXDIDXCMDTNVYG/","label":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/DISZAFSIQ7IAPAEQTC7G2Z5QUA2V2PSW/","label":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/HPX4XHT2FGVQYLY2STT2MRVENILNZTTU/","label":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/I3MQT5ZE3QH5PVDJMERTBOCILHK35CBE/","label":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/IFGV7P2PYFBMK32OKHCAC2ZPJQV5AUDF/","label":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/KRGKPYA5YHIXQAMRIXO5DSCX7D4UUW4Q/","label":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/OKYE2DOI2X7WZXAWTQJZAXYIWM37HDCY/","label":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/QLE5INSVJUZJGY5OJXV6JREXWD7UDHYN/","label":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/S7G66SRWUM36ENQ3X6LAIG7HAB27D4XJ/","label":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TZEPOPUFC42KXXSLFPZ47ZZRGPOR7SQE/","label":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WXF6MQ74HVIDDSR5AE2UDR24I6D4FEPC/","label":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/X46T4EFTIBXZRYTGASBDEZGYJINH2OWV/","label":"cve@mitre.org"},{"url":"https://security.gentoo.org/glsa/202305-02","label":"cve@mitre.org"},{"url":"https://bugs.python.org/issue43223","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://github.com/python/cpython/pull/24848","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://github.com/python/cpython/pull/93879","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.debian.org/debian-lts-announce/2024/11/msg00024.html","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.debian.org/debian-lts-announce/2024/12/msg00000.html","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/2TRINJE3INWDVIHIABW4L2NP3RUSK7BJ/","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5LTSPFIULY2GZJN3QYNFVM4JSU6H4D6J/","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5OABQ5CMPQETJLFHROAXDIDXCMDTNVYG/","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/DISZAFSIQ7IAPAEQTC7G2Z5QUA2V2PSW/","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/HPX4XHT2FGVQYLY2STT2MRVENILNZTTU/","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/I3MQT5ZE3QH5PVDJMERTBOCILHK35CBE/","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/IFGV7P2PYFBMK32OKHCAC2ZPJQV5AUDF/","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/KRGKPYA5YHIXQAMRIXO5DSCX7D4UUW4Q/","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/OKYE2DOI2X7WZXAWTQJZAXYIWM37HDCY/","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/QLE5INSVJUZJGY5OJXV6JREXWD7UDHYN/","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/S7G66SRWUM36ENQ3X6LAIG7HAB27D4XJ/","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TZEPOPUFC42KXXSLFPZ47ZZRGPOR7SQE/","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WXF6MQ74HVIDDSR5AE2UDR24I6D4FEPC/","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/X46T4EFTIBXZRYTGASBDEZGYJINH2OWV/","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://security.gentoo.org/glsa/202305-02","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-398330.html","label":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"}],"tags":["nvd"],"epss":0.02535,"epssPercentile":0.84546,"ingestedAt":"2026-10-14T12:29:10.829Z","slug":"CVE-2021-28861","body":"## Overview\n\nPython 3.x through 3.10 has an open redirection vulnerability in lib/http/server.py due to no protection against multiple (/) at the beginning of URI path which may leads to information disclosure. NOTE: this is disputed by a third party because the http.server.html documentation page states \"Warning: http.server is not recommended for production. It only implements basic security checks.\"\n\n## Affected\n\n- `python >= 3.0.0, < 3.7.14`\n- `python >= 3.8.0, < 3.8.14`\n- `python >= 3.9.0, < 3.9.14`\n- `python >= 3.10.0, < 3.10.6`\n- `python = 3.11.0`\n- `fedora = 35`\n- `fedora = 36`\n- `fedora = 37`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `python 3.10.6`","depth":"twilight","depthScore":41,"depthScoreParts":{"impact":40.7,"likelihood":0.5,"exploitation":0,"ransomware":0},"changes":[]}