---
id: CVE-2023-29483
aliases:
  - GHSA-3rq5-2g8h-59hc
  - PYSEC-2026-1307
  - PYSEC-2026-2472
title: Potential DoS via the Tudoor mechanism in eventlet and dnspython
summary: Potential DoS via the Tudoor mechanism in eventlet and dnspython
severity: medium
cvss: 5.9
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H'
vendor: eventlet
product: eventlet
ecosystem: pip
affected:
  - eventlet < 0.35.2
  - dnspython < 2.6.1
patched:
  - eventlet 0.35.2
  - dnspython 2.6.1
published: '2024-04-11'
updated: '2026-09-10'
sourceUpdated: '2026-09-10T03:50:11.305148352Z'
source: OSV
sourceUrl: 'https://osv.dev/vulnerability/GHSA-3rq5-2g8h-59hc'
references:
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2023-29483'
  - url: 'https://github.com/eventlet/eventlet/issues/913'
  - url: 'https://github.com/rthalley/dnspython/issues/1045'
  - url: >-
      https://github.com/eventlet/eventlet/commit/51e3c4928d4938beb576eff34f3bf97e6e64e6b4
  - url: >-
      https://github.com/rthalley/dnspython/commit/0ea5ad0a4583e1f519b9bcc67cfac381230d9cf2
  - url: 'https://github.com/eventlet/eventlet'
  - url: 'https://github.com/eventlet/eventlet/releases/tag/v0.35.2'
  - url: 'https://github.com/rthalley/dnspython/releases/tag/v2.6.0'
  - url: >-
      https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/NLRKR57IFVKQC2GCXZBFLCLBAWBWL3F6
  - url: >-
      https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VOHJOO3OM65UIUUUVDEXMCTXNM6LXZEH
  - url: >-
      https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/X3BNSIK5NFYSAP53Y45GOCMOQHHDLGIF
  - url: 'https://security.netapp.com/advisory/ntap-20240510-0001'
  - url: 'https://security.snyk.io/vuln/SNYK-PYTHON-DNSPYTHON-6241713'
  - url: 'https://www.dnspython.org'
tags:
  - osv
  - pip
epss: 0.01857
epssPercentile: 0.78305
ingestedAt: '2026-07-08T18:25:44.953Z'
---

## Overview

eventlet before 0.35.2, as used in dnspython before 2.6.0, allows remote attackers to interfere with DNS name resolution by quickly sending an invalid packet from the expected IP address and source port, aka a "TuDoor" attack. In other words, dnspython does not have the preferred behavior in which the DNS name resolution algorithm would proceed, within the full time window, in order to wait for a valid packet. NOTE: dnspython 2.6.0 is unusable for a different reason that was addressed in 2.6.1.

## Affected packages

- `eventlet < 0.35.2`
- `dnspython < 2.6.1`

## Remediation

Upgrade to a patched release:

- `eventlet 0.35.2`
- `dnspython 2.6.1`