Vulnerability-Lookup

ubuntu-cve-2026-71218

Vulnerability from osv_ubuntu

Published

2026-08-13 00:00

Modified

2026-08-13 00:00

Summary

Details

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.

Severity

5.3 (Medium)


                    
                      CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

N/A (UNKNOWN)


                    
                      medium

References

URL

Type

	https://ubuntu.com/security/CVE-2026-71218	REPORT
	https://www.cve.org/CVERecord?id=CVE-2026-71218	REPORT
	https://github.com/esnet/iperf/commit/0128d0357b7…	REPORT
	https://bugzilla.redhat.com/show_bug.cgi?id=2463003	REPORT
	https://access.redhat.com/security/cve/CVE-2026-71218	REPORT
	https://github.com/esnet/iperf/commit/0128d0357b7…	REPORT

JSON

To clipboard

{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "iperf3",
            "binary_version": "3.0.11-1ubuntu0.1~esm2"
          },
          {
            "binary_name": "libiperf0",
            "binary_version": "3.0.11-1ubuntu0.1~esm2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:16.04:LTS",
        "name": "iperf3",
        "purl": "pkg:deb/ubuntu/iperf3@3.0.11-1ubuntu0.1~esm2?arch=source\u0026distro=esm-apps/xenial"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.0.11-1",
        "3.0.11-1ubuntu0.1~esm1",
        "3.0.11-1ubuntu0.1~esm2"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "iperf3",
            "binary_version": "3.1.3-1ubuntu0.1~esm1"
          },
          {
            "binary_name": "libiperf0",
            "binary_version": "3.1.3-1ubuntu0.1~esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:18.04:LTS",
        "name": "iperf3",
        "purl": "pkg:deb/ubuntu/iperf3@3.1.3-1ubuntu0.1~esm1?arch=source\u0026distro=esm-apps/bionic"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.1.3-1",
        "3.1.3-1ubuntu0.1~esm1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "iperf3",
            "binary_version": "3.7-3ubuntu0.1~esm2"
          },
          {
            "binary_name": "libiperf0",
            "binary_version": "3.7-3ubuntu0.1~esm2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:20.04:LTS",
        "name": "iperf3",
        "purl": "pkg:deb/ubuntu/iperf3@3.7-3ubuntu0.1~esm2?arch=source\u0026distro=esm-apps/focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.6-2",
        "3.7-1",
        "3.7-2",
        "3.7-3",
        "3.7-3ubuntu0.1~esm1",
        "3.7-3ubuntu0.1~esm2"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "iperf3",
            "binary_version": "3.9-1+deb11u1ubuntu0.1"
          },
          {
            "binary_name": "libiperf0",
            "binary_version": "3.9-1+deb11u1ubuntu0.1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:22.04:LTS",
        "name": "iperf3",
        "purl": "pkg:deb/ubuntu/iperf3@3.9-1+deb11u1ubuntu0.1?arch=source\u0026distro=esm-apps/jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.9-1",
        "3.9-1build1",
        "3.9-1+deb11u1build0.22.04.1",
        "3.9-1+deb11u1ubuntu0.1~esm1",
        "3.9-1+deb11u1ubuntu0.1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "iperf3",
            "binary_version": "3.16-1ubuntu0.1~esm1"
          },
          {
            "binary_name": "libiperf0",
            "binary_version": "3.16-1ubuntu0.1~esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:24.04:LTS",
        "name": "iperf3",
        "purl": "pkg:deb/ubuntu/iperf3@3.16-1ubuntu0.1~esm1?arch=source\u0026distro=esm-apps/noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.14-1",
        "3.15-1",
        "3.16-1",
        "3.16-1build1",
        "3.16-1build2",
        "3.16-1ubuntu0.1~esm1"
      ]
    }
  ],
  "aliases": [],
  "details": "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.",
  "id": "UBUNTU-CVE-2026-71218",
  "modified": "2026-08-13T00:00:00Z",
  "published": "2026-08-13T00:00:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-71218"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-71218"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/esnet/iperf/commit/0128d0357b7e8916fe39e980e455729bc0e5fd4e"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2463003"
    },
    {
      "type": "REPORT",
      "url": "https://access.redhat.com/security/cve/CVE-2026-71218"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/esnet/iperf/commit/0128d0357b7e8916fe39e980e455729bc0e5fd4e"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L",
      "type": "CVSS_V3"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2026-71218"
  ]
}

CVE-2026-71218 (GCVE-0-2026-71218)

Vulnerability from cvelistv5 – Published: 2026-08-11 08:51 – Updated: 2026-08-11 13:00

Title

Iperf3: unbounded peer-controlled allocation in iperf3 json_read() allows unauthenticated remote memory exhaustion

Summary

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.

Severity

5.3 (Medium)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-08-11 12:54 UTC

CWE

CWE-789 - Memory Allocation with Excessive Size Value

Assigner

redhat

References

3 references

URL	Tags
https://access.redhat.com/security/cve/CVE-2026-71218	vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2463003	issue-trackingx_refsource_REDHAT
https://github.com/esnet/iperf/commit/0128d0357b7…

Impacted products

4 products

Vendor	Product	Version
Red Hat	Red Hat Enterprise Linux 10	cpe:/o:redhat:enterprise_linux:10
Red Hat	Red Hat Enterprise Linux 7	cpe:/o:redhat:enterprise_linux:7
Red Hat	Red Hat Enterprise Linux 8	cpe:/o:redhat:enterprise_linux:8
Red Hat	Red Hat Enterprise Linux 9	cpe:/o:redhat:enterprise_linux:9

Date Public

2026-08-11 08:13

Credits

This issue was discovered by Found by AISLE in partnership with Red Hat.

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-71218",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-08-11T12:54:34.803644Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-08-11T13:00:19.528Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "cpes": [
            "cpe:/o:redhat:enterprise_linux:10"
          ],
          "defaultStatus": "affected",
          "packageName": "iperf3",
          "product": "Red Hat Enterprise Linux 10",
          "vendor": "Red Hat"
        },
        {
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "cpes": [
            "cpe:/o:redhat:enterprise_linux:7"
          ],
          "defaultStatus": "affected",
          "packageName": "iperf3",
          "product": "Red Hat Enterprise Linux 7",
          "vendor": "Red Hat"
        },
        {
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "cpes": [
            "cpe:/o:redhat:enterprise_linux:8"
          ],
          "defaultStatus": "affected",
          "packageName": "iperf3",
          "product": "Red Hat Enterprise Linux 8",
          "vendor": "Red Hat"
        },
        {
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "cpes": [
            "cpe:/o:redhat:enterprise_linux:9"
          ],
          "defaultStatus": "affected",
          "packageName": "iperf3",
          "product": "Red Hat Enterprise Linux 9",
          "vendor": "Red Hat"
        }
      ],
      "credits": [
        {
          "lang": "en",
          "value": "This issue was discovered by Found by AISLE in partnership with Red Hat."
        }
      ],
      "datePublic": "2026-08-11T08:13:07.439Z",
      "descriptions": [
        {
          "lang": "en",
          "value": "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."
        }
      ],
      "metrics": [
        {
          "other": {
            "content": {
              "namespace": "https://access.redhat.com/security/updates/classification/",
              "value": "Moderate"
            },
            "type": "Red Hat severity rating"
          }
        },
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "LOW",
            "baseScore": 5.3,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "NONE",
            "integrityImpact": "NONE",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L",
            "version": "3.1"
          },
          "format": "CVSS"
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-789",
              "description": "Memory Allocation with Excessive Size Value",
              "lang": "en",
              "type": "CWE"
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      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-11T10:20:34.420Z",
        "orgId": "53f830b8-0a3f-465b-8143-3b8a9948e749",
        "shortName": "redhat"
      },
      "references": [
        {
          "tags": [
            "vdb-entry",
            "x_refsource_REDHAT"
          ],
          "url": "https://access.redhat.com/security/cve/CVE-2026-71218"
        },
        {
          "name": "RHBZ#2463003",
          "tags": [
            "issue-tracking",
            "x_refsource_REDHAT"
          ],
          "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2463003"
        },
        {
          "url": "https://github.com/esnet/iperf/commit/0128d0357b7e8916fe39e980e455729bc0e5fd4e"
        }
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      "timeline": [
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          "lang": "en",
          "time": "2026-04-26T20:37:37.000Z",
          "value": "Reported to Red Hat."
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          "lang": "en",
          "time": "2026-08-11T08:13:07.439Z",
          "value": "Made public."
        }
      ],
      "title": "Iperf3: unbounded peer-controlled allocation in iperf3 json_read() allows unauthenticated remote memory exhaustion",
      "workarounds": [
        {
          "lang": "en",
          "value": "To mitigate this issue, restrict network access to the `iperf3` control port, ensuring it is only reachable by trusted clients. This can be achieved by configuring firewall rules to limit inbound connections to the `iperf3` service. Additionally, consider running the `iperf3` service within environments that enforce process or container memory limits to further contain potential resource exhaustion. Note that authentication alone is insufficient as the memory allocation occurs before authentication checks."
        }
      ],
      "x_generator": {
        "engine": "cvelib 1.8.0"
      },
      "x_redhatCweChain": "CWE-789: Memory Allocation with Excessive Size Value"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "53f830b8-0a3f-465b-8143-3b8a9948e749",
    "assignerShortName": "redhat",
    "cveId": "CVE-2026-71218",
    "datePublished": "2026-08-11T08:51:24.805Z",
    "dateReserved": "2026-08-05T08:41:54.899Z",
    "dateUpdated": "2026-08-11T13:00:19.528Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.

Action not permitted

ubuntu-cve-2026-71218

Vulnerability from osv_ubuntu

CVE-2026-71218 (GCVE-0-2026-71218)

Tags

Sightings

Nomenclature