Python up to 3.10 lib/http/server.py path traversal ⚔ [Disputed]

CVSS Meta Temp Score
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CTI Interest Score
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5.7$0-$5k0.00

Summaryinfo

A vulnerability marked as critical has been reported in Python up to 3.10. Impacted is an unknown function in the library lib/http/server.py. This manipulation causes path traversal. The identification of this vulnerability is CVE-2021-28861. There is no exploit available. There are still doubts about whether this vulnerability truly exists. It is recommended to apply a patch to fix this issue.

Detailsinfo

A vulnerability has been found in Python up to 3.10 (Programming Language Software) and classified as critical. Affected by this vulnerability is an unknown code in the library lib/http/server.py. The manipulation with an unknown input leads to a path traversal vulnerability. The CWE definition for the vulnerability is CWE-22. The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory. As an impact it is known to affect confidentiality. The summary by CVE is:

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."

The weakness was shared 08/23/2022. It is possible to read the advisory at github.com. This vulnerability is known as CVE-2021-28861 since 03/19/2021. Technical details of the vulnerability are known, but there is no available exploit. The attack technique deployed by this issue is T1006 according to MITRE ATT&CK.

The real existence of this vulnerability is still doubted at the moment. The vulnerability scanner Nessus provides a plugin with the ID 211341 (Fedora 38 : python3.6 (2022-2e93acb55d)), which helps to determine the existence of the flaw in a target environment.

Applying a patch is able to eliminate this problem. The bugfix is ready for download at github.com.

The vulnerability is also documented in the databases at Tenable (211341) and CERT Bund (WID-SEC-2022-1150). Be aware that VulDB is the high quality source for vulnerability data.

Affected

  • Debian Linux
  • Amazon Linux 2
  • Red Hat Enterprise Linux
  • Fedora Linux
  • Ubuntu Linux
  • SUSE Linux
  • Oracle Linux
  • EMC Avamar
  • Open Source Python
  • IBM QRadar SIEM
  • Red Hat OpenShift
  • RESF Rocky Linux
  • Dell NetWorker

Productinfo

Type

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.8
VulDB Meta Temp Score: 5.7

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.4
NVD Vector: 🔍

CVSSv2info

AVACAuCIA
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💳💳💳💳💳💳
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Path traversal
CWE: CWE-22
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 211341
Nessus Name: Fedora 38 : python3.6 (2022-2e93acb55d)

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔍

Patch: github.com

Timelineinfo

03/19/2021 🔍
08/23/2022 +521 days 🔍
08/23/2022 +0 days 🔍
12/21/2025 +1216 days 🔍

Sourcesinfo

Advisory: FEDORA-2022-f511f8f58b
Status: Confirmed
Disputed: 🔍

CVE: CVE-2021-28861 (🔍)
GCVE (CVE): GCVE-0-2021-28861
GCVE (VulDB): GCVE-100-206959
CERT Bund: WID-SEC-2022-1150 - Python: Schwachstelle ermöglicht Offenlegung von Informationen

Entryinfo

Created: 08/23/2022 07:31
Updated: 12/21/2025 20:15
Changes: 08/23/2022 07:31 (40), 09/24/2022 13:33 (1), 08/04/2024 01:14 (28), 11/15/2024 11:28 (3), 11/05/2025 08:35 (1), 12/21/2025 20:15 (7)
Complete: 🔍
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

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