CVE-2026-71218
Status: Awaiting AnalysisMedium (5.3)—
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
- Version: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
- Base score: 5.3
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days: 0.67%
- Percentile among all scored CVEs: 50
- Score date: 9/30/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
Affected technologies (1)
⚠ AI-inferred from the description — NVD hasn't analyzed this CVE yet, these aren't verified CPEs.
CWEs
- CWE-789
References
Raw JSON (NVD)
Show
{
"id": "CVE-2026-71218",
"cveTags": [],
"metrics": {
"ssvcV203": [
{
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"id": "CVE-2026-71218",
"role": "CISA Coordinator",
"options": [
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"exploitation": "none"
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{
"automatable": "yes"
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{
"technicalImpact": "partial"
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"version": "2.0.3",
"timestamp": "2026-08-11T12:54:34.803644Z"
}
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"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L",
"integrityImpact": "NONE",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "LOW",
"privilegesRequired": "NONE",
"confidentialityImpact": "NONE"
},
"impactScore": 1.4,
"exploitabilityScore": 3.9
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"packageName": "iperf3",
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"published": "2026-08-11T09:17:14.200",
"references": [
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{
"url": "https://bugzilla.redhat.com/show_bug.cgi?id=2463003",
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"url": "https://github.com/esnet/iperf/commit/0128d0357b7e8916fe39e980e455729bc0e5fd4e",
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"description": [
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"lastModified": "2026-08-14T19:07:46.080",
"sourceIdentifier": "secalert@redhat.com"
}