Medium 6.5Published Aug 22, 2022

CVE-2021-28861Python 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.

Updated under an hour ago (Oct 28, 2026, 7:30 AM ET)

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It affects Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP and 4 other products. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

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Every CVE for Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP

Exploited in the last 30 days

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 because the http.server.html documentation page states "Warning: http.server is not recommended for production. It only implements basic security checks."

CVSS: 6.5 MEDIUM (v3.1, CISA ADP)CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
Weakness (CWE): CWE-601
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: mitre
NVD analysis: Modified
Record last updated: Oct 14, 2026
First seen by InfoSec Signals: Oct 14, 2026

Affected products

Affected products

Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP siemens:simatic_s7_1500_cpu_1518_4_pn_dp_mfp (from the name)	from V3.1.0 before V3.1.5	CISA ADP
Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP siemens:simatic_s7_1500_cpu_1518f_4_pn_dp_mfp (from the name)	from V3.1.0 before V3.1.5	CISA ADP
Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP siemens:siplus_s7_1500_cpu_1518_4_pn_dp_mfp (from the name)	from V3.1.0 before V3.1.5	CISA ADP
python python python:python	from 3.0.0 before 3.7.14; from 3.8.0 before 3.8.14; from 3.9.0 before 3.9.14; from 3.10.0 before 3.10.6; 3.11.0; 3.11.0; 3.11.0; 3.11.0; and 6 more ranges	NVD
fedoraproject fedora fedoraproject:fedora	35; 36; 37	NVD

References

References

https://bugs.python.org/issue43223	issue-tracking, vendor-advisory
https://github.com/python/cpython/pull/93879	patch, third-party-advisory
https://github.com/python/cpython/pull/24848	patch, third-party-advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/OKYE2DOI2X7WZXAWTQJZAXYIWM37HDCY/	vendor-advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5LTSPFIULY2GZJN3QYNFVM4JSU6H4D6J/	vendor-advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/S7G66SRWUM36ENQ3X6LAIG7HAB27D4XJ/	vendor-advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/DISZAFSIQ7IAPAEQTC7G2Z5QUA2V2PSW/	vendor-advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/QLE5INSVJUZJGY5OJXV6JREXWD7UDHYN/	vendor-advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/HPX4XHT2FGVQYLY2STT2MRVENILNZTTU/	vendor-advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/X46T4EFTIBXZRYTGASBDEZGYJINH2OWV/	vendor-advisory
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The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.