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TI-2021-17419 Aliases CVE-2021-40347GHSA-v83x-78q3-gr2j

An issue was discovered in views/list.py in GNU Mailman Postorius before 1.3.5.

Priority LOW 27CWE-284Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
Low · Low · None
Fix status
Fixed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and GitHub. Impact type from CWE-284.

Summary

An issue was discovered in views/list.py in GNU Mailman Postorius before 1.3.5. An attacker (logged into any account) can send a crafted POST request to unsubscribe any user from a mailing list, also revealing whether that address was subscribed in the first place.

Why it matters now

EPSS 0.01209 68th percentileScored 2026-11-07
Public exploit Yes 2 exploit referencesTagged by NVD
Fix Fixed postorius (PyPI): 1.3.5

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
——all versions—No fix listedCNA
—postorius (PyPI)before 1.3.51.3.5Patch availableGHSA-v83x-78q3-gr2j
  • — Vendor— Affected all versions Fixed in — No fix listed CNA
  • postorius (PyPI) Vendor— Affected before 1.3.5 Fixed in 1.3.5 Patch available GHSA-v83x-78q3-gr2j

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:postorius_project:postorius:*:*:*:*:*:*:*:*before 1.3.5VulnerablePostorius project
  • cpe:2.3:a:postorius_project:postorius:*:*:*:*:*:*:*:* Versions before 1.3.5 Vulnerable ·Postorius project

Remediation

  • Fix · GHSA-v83x-78q3-gr2j postorius (PyPI) Fixed in 1.3.5 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-40347
  2. 2026-10-03 Alias added: GHSA-v83x-78q3-gr2j

References

Exploit 2

Patch 1

Advisory 4

Other 2

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences