CVE-2026-101276 - Vulnerability Details - OpenCVE

Description

iperf3 3.21 (esnet/iperf) contains a remote, unauthenticated heap use-after-free: the server's per-test watchdog server_timer_proc() frees streams without cancelling/joining their worker threads, so a blocked worker dereferences a freed iperf_stream; fixed in 3.22.

Published: 2026-09-30

Score: 9.2 Critical

EPSS: n/a

KEV: No

Impact:

Action:

Analysis

No analysis available yet.

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

esnet

iperf3

unaffected

Version	Status	Constraints
`3.21`	affected	—

No data.

No data.

No data available yet.

Remediation

No remediation available yet.

Tracking

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Advisories

No advisories yet.

Attack Vector Network

Attack Complexity Low

Privileges Required None

Attack Requirements Present

User Interaction None

Vulnerable System Confidentiality Impact High

Vulnerable System Integrity Impact High

Vulnerable System Availability Impact High

Subsequent System Confidentiality Impact None

Subsequent System Integrity Impact None

Subsequent System Availability Impact None

No CVSS v3.1

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Key SSVC decision points have not yet been added.

References

Link	Providers
https://newreleases.io/project/github/esnet/iperf/release/3.22

History

Wed, 30 Sep 2026 21:15:00 +0000

Type	Values Removed	Values Added
Description		iperf3 3.21 (esnet/iperf) contains a remote, unauthenticated heap use-after-free: the server's per-test watchdog server_timer_proc() frees streams without cancelling/joining their worker threads, so a blocked worker dereferences a freed iperf_stream; fixed in 3.22.
Weaknesses		CWE-416
References		https://newreleases.io/project/github/esnet/iperf/release/3.22
Metrics		cvssV4_0 `{'score': 9.2, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N'}`

Subscriptions

No data.

MITRE

Status: PUBLISHED

Assigner: Anthropic

Published: 2026-09-30T21:11:52.046Z

Updated: 2026-09-30T21:13:21.540Z

Reserved: 2026-09-28T11:52:18.066Z

Link: CVE-2026-101276

Vulnrichment

No data.

NVD

Status : Received

Published: 2026-09-30T21:16:54.913

Modified: 2026-09-30T21:16:54.913

Link: CVE-2026-101276

Redhat

No data.

OpenCVE Enrichment

No data.

Weaknesses

CWE-416
Use After Free

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