CVE-2026-102253

HIGH 7.5

iperf3 < 3.22 UDP Receive Worker Infinite Loop DoS

CVSS Score

7.5

EPSS Score

0.0%

EPSS Percentile

0th

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.

CWE	CWE-835
Vendor	esnet
Product	iperf3
Published	Sep 29, 2026

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CVSS v3 Breakdown

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

Affected Versions

esnet / iperf3

3.14 < 3.22

References

NVD ↗ CVE.org ↗ EPSS Data ↗

github.com: https://github.com/esnet/iperf/releases/tag/3.22 github.com: https://github.com/esnet/iperf/blob/master/RELNOTES.md vulncheck.com: https://www.vulncheck.com/advisories/iperf3-udp-receive-worker-infinite-loop-dos

Credits

Ravindu Lakmina Munaweera VulnCheck