CVE-2026-71218

A flaw was found in iperf3. A remote unauthenticated attacker can exploit a vulnerability in the `JSON_read()` function, which accepts a peer-controlled message length and allocates memory without an upper bound. This allows the attacker to trigger excessive memory consumption, leading to a Denial of Service (DoS) through memory exhaustion, severe slowdown, or termination of the iperf3 service.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://access.redhat.com/security/cve/CVE-2026-71218
https://bugzilla.redhat.com/show_bug.cgi?id=2463003
https://github.com/esnet/iperf/commit/0128d0357b7e8916fe39e980e455729bc0e5fd4e

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-11 09:17

Updated : 2026-08-14 19:07

NVD link : CVE-2026-71218

Mitre link : CVE-2026-71218

CVE.ORG link : CVE-2026-71218

JSON object : View

Products Affected

No product.

CWE

CWE-789

Memory Allocation with Excessive Size Value

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