Description
There's a flaw in Python 3's pydoc. A local or adjacent attacker who discovers or is able to convince another local or adjacent user to start a pydoc server could access the server and use it to disclose sensitive information belonging to the other user that they would not normally be able to access. The highest risk of this flaw is to data confidentiality. This flaw affects Python versions before 3.8.9, Python versions before 3.9.3 and Python versions before 3.10.0a7.
Published: 2021-05-20
Score: 5.7 Medium
EPSS: < 1% Very Low
KEV: No
Impact: n/a
Action: n/a
AI Analysis

No analysis available yet.

Remediation

No remediation available yet.

Tracking

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Advisories
Source ID Title
Debian DLA Debian DLA DLA-2619-1 python3.5 security update
Debian DLA Debian DLA DLA-3477-1 python3.7 security update
Debian DLA Debian DLA DLA-3980-1 python3.9 security update
EUVD EUVD EUVD-2021-26753 There's a flaw in Python 3's pydoc. A local or adjacent attacker who discovers or is able to convince another local or adjacent user to start a pydoc server could access the server and use it to disclose sensitive information belonging to the other user that they would not normally be able to access. The highest risk of this flaw is to data confidentiality. This flaw affects Python versions before 3.8.9, Python versions before 3.9.3 and Python versions before 3.10.0a7.
Ubuntu USN Ubuntu USN USN-5342-1 Python vulnerabilities
Ubuntu USN Ubuntu USN USN-5342-3 Python vulnerability
Ubuntu USN Ubuntu USN USN-6891-1 Python vulnerabilities
References
History

Thu, 18 Dec 2025 12:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Mon, 03 Nov 2025 22:30:00 +0000

Type Values Removed Values Added
References

Mon, 14 Jul 2025 13:45:00 +0000

Type Values Removed Values Added
Metrics epss

{'score': 0.00109}

epss

{'score': 0.00098}


Fri, 11 Jul 2025 13:45:00 +0000

Type Values Removed Values Added
Metrics epss

{'score': 0.00095}

epss

{'score': 0.00109}


Subscriptions

Debian Debian Linux
Fedoraproject Fedora
Netapp Cloud Backup Ontap Select Deploy Administration Utility Snapcenter
Oracle Communications Cloud Native Core Binding Support Function Zfs Storage Appliance Kit
Python Python
Redhat Enterprise Linux Rhel Software Collections Software Collections
cve-icon MITRE

Status: PUBLISHED

Assigner: redhat

Published:

Updated: 2025-12-18T11:45:56.551Z

Reserved: 2021-03-09T00:00:00.000Z

Link: CVE-2021-3426

cve-icon Vulnrichment

Updated: 2025-11-03T21:44:51.975Z

cve-icon NVD

Status : Modified

Published: 2021-05-20T13:15:07.753

Modified: 2025-12-18T12:15:54.153

Link: CVE-2021-3426

cve-icon Redhat

Severity : Moderate

Publid Date: 2021-03-10T00:00:00Z

Links: CVE-2021-3426 - Bugzilla

cve-icon OpenCVE Enrichment

No data.

Weaknesses