Vulnerability in iperf3 (CVE-2026-71217)
Summary
Vulnerability in iperf3 (CVE-2026-71217). Risk of unauthorized operations or information disclosure. Exploitable via parallel.
Original description
The description as published by the source.
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.
Source: GitHub Security Advisories (Global) NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-71217 has been found in iperf3.
Attackers can target a specific entry point like parallel over the network to misuse the product.
Risk of unauthorized operations or information disclosure. CVSS score: 7.5/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "iperf3 CVE-2026-71217" on the vendor's site.
CVE-2026-71217 (iperf3) — CWE-20 / CVSS v3 7.5
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Attack surface: parallel / len
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-20) exists in iperf3. Attackers reach the vulnerable code path via parallel without authentication.
Check the vendor advisory for the affected versions of iperf3. Attack surface: parallel / len.
Severity: High (CVSS 7.5/10). Risk of unauthorized operations or information disclosure.
Update to the patched release per vendor advisory.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'iperf3' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r 'iperf3' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
iperf3を grep し、稼働しているサービス・バージョンを把握する。 -
2Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Fix status by distribution
Fixed packages published by each distribution for this CVE
- BellSoft Alpaquita BELL-CVE-2026-71217 iperf3 Fixed in: 3.22-r0
- Debian DEBIAN-CVE-2026-71217 iperf3
- Ubuntu UBUNTU-CVE-2026-71217 iperf3
References
- web nvd.nist.gov
- web access.redhat.com
- web bugzilla.redhat.com
- web github.com
- web github.com
- web access.redhat.com
- web access.redhat.com
- web access.redhat.com