---
id: CVE-2026-102253
title: >-
  iperf3 versions prior to 3.22 contains a denial of service vulnerability that
  allows unauthenticated remote attackers to crash-loop the server's UDP receive
  worker into an unrecoverable infinite loop by sending a single crafted
  control-c…
summary: >-
  iperf3 versions prior to 3.22 contains a denial of service vulnerability that
  allows unauthenticated remote attackers to crash-loop the server's UDP receive
  worker into an unrecoverable infinite loop by sending a single crafted
  control-c…
severity: high
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'
cwe:
  - CWE-835
vendor: esnet
product: iperf3
affected:
  - iperf3 >= 3.14 < 3.22
published: '2026-09-29'
updated: '2026-09-30'
sourceUpdated: '2026-09-30T20:17:21.840'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-102253'
references:
  - url: 'https://github.com/esnet/iperf/blob/master/RELNOTES.md'
    label: disclosure@vulncheck.com
  - url: 'https://github.com/esnet/iperf/releases/tag/3.22'
    label: disclosure@vulncheck.com
  - url: >-
      https://www.vulncheck.com/advisories/iperf3-udp-receive-worker-infinite-loop-dos
    label: disclosure@vulncheck.com
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-102253.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-102253'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2543638'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-102253'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-102253'
tags:
  - nvd
  - cve.org
  - csaf
  - vex
  - red-hat
  - exploit-available
ssvc:
  exploitation: none
  automatable: 'yes'
  technicalImpact: partial
  timestamp: '2026-09-30T19:25:42.477583Z'
epss: 0.00431
epssPercentile: 0.37112
ingestedAt: '2026-09-29T20:46:06.617Z'
exploits:
  github: 1
  githubRepos:
    - 'https://github.com/Ravi-lk/CVE-2026-102253-POC'
  checkedAt: '2026-10-27T16:53:21.676Z'
exploitAvailable: true
---

## Overview

iperf3 versions prior to 3.22 contains a denial of service vulnerability that allows unauthenticated remote attackers to crash-loop the server's UDP receive worker into an unrecoverable infinite loop by sending a single crafted control-channel parameter message followed by one 16-byte UDP datagram. Attackers can permanently pin the affected per-stream receive thread at approximately 100% CPU usage, rendering the server unusable until forcibly killed with SIGKILL, as the process does not respond to normal control-channel closure.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

## Vendor advisories

- **Red Hat VEX** · Important · affected: Red Hat Enterprise Linux 10 · no fix planned: Red Hat Enterprise Linux 10 · updated 2026-10-01 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-102253.json)