Iperf3: iperf3 server accepts unbounded peer-controlled json parameters enabling remote denial of service via resource exhaustion
41Vexday Risk Score
No sign of exploitation. It has a public proof of concept.
ssvc Attendcvss 7.5epss 0.6%
from disclosure to weapon40 days
Published on NVDAug 11
1st PoC+40d
exploitation probability
0.6%top 53% of all CVEs
observed exploitation
nono source reports it
1 public exploit(s)
A flaw was found in iperf3. A remote attacker can exploit this vulnerability by sending crafted control-channel JSON with oversized numeric parameters, such as `parallel` and `len`, which are not properly validated by the server. This improper input validation can lead to excessive stream and thread creation, as well as large buffer allocations, causing resource exhaustion. Consequently, this can result in a Denial of Service (DoS) on the affected iperf3 server.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Affected products
Red Hat · Red Hat Enterprise Linux 10Red Hat · Red Hat Enterprise Linux 7Red Hat · Red Hat Enterprise Linux 8Red Hat · Red Hat Enterprise Linux 9public PoCs found — 1
githubgithub.com/Reelix/CVE-2026-71217-PoC★ 1⚠ Public resources, to assess the exposure of systems you control or are authorized to test. Test only with authorization.
References
https://access.redhat.com/errata/RHSA-2026:61257https://access.redhat.com/errata/RHSA-2026:61389https://access.redhat.com/errata/RHSA-2026:61680https://access.redhat.com/security/cve/CVE-2026-71217https://bugzilla.redhat.com/show_bug.cgi?id=2460984https://github.com/esnet/iperf/commit/494dd377eca4689672becdf06a85158557db1586