Vulnerability-Lookup

Vulnerability from bitnami_vulndb

Published

2026-09-19 08:51

Modified

2026-09-19 09:02

Summary

Apache ZooKeeper: Improper validation of certificate with host mismatch in FIPS mode

Details

Apache ZooKeeper quorum TLS fails to enforce peer hostname verification in FIPS-mode deployments. When sslQuorum=true, zookeeper.fips-mode=true, ssl.quorum.hostnameVerification=true, and ssl.quorum.clientHostnameVerification=true are enabled, the Java SSLSocket quorum path accepts a CA-trusted peer certificate whose SAN does not match the connected host. A malicious or misissued peer certificate can therefore join quorum traffic, participate in leader election, and enter replication flows.

Users are recommended to upgrade to version 3.8.7 or 3.9.6, which fixes the issue.

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "Bitnami",
        "name": "zookeeper",
        "purl": "pkg:bitnami/zookeeper"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "3.8.0"
            },
            {
              "fixed": "3.8.7"
            },
            {
              "introduced": "3.9.0"
            },
            {
              "fixed": "3.9.6"
            }
          ],
          "type": "SEMVER"
        }
      ],
      "severity": [
        {
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N",
          "type": "CVSS_V3"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-59969"
  ],
  "database_specific": {
    "cpes": [
      "cpe:2.3:a:apache:zookeeper:*:*:*:*:*:*:*:*"
    ],
    "severity": "High"
  },
  "details": "Apache ZooKeeper quorum TLS fails to enforce peer hostname verification in FIPS-mode deployments. When sslQuorum=true, zookeeper.fips-mode=true, ssl.quorum.hostnameVerification=true, and ssl.quorum.clientHostnameVerification=true\u00a0are enabled, the Java SSLSocket\u00a0quorum path accepts a CA-trusted peer certificate whose SAN does not match the connected host. A malicious or misissued peer certificate can therefore join quorum traffic, participate in leader election, and enter replication flows.\n\n\n\nUsers are recommended to upgrade to version 3.8.7 or 3.9.6, which fixes the issue.",
  "id": "BIT-zookeeper-2026-59969",
  "modified": "2026-09-19T09:02:05.474Z",
  "published": "2026-09-19T08:51:28.283Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "http://www.openwall.com/lists/oss-security/2026/09/15/4"
    },
    {
      "type": "ADVISORY",
      "url": "https://lists.apache.org/thread/qf9kwsgtgbgtvwls6f41281846xg0rss"
    },
    {
      "type": "WEB",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-59969"
    }
  ],
  "schema_version": "1.6.2",
  "summary": "Apache ZooKeeper: Improper validation of certificate with host mismatch in FIPS mode"
}

CVE-2026-59969 (GCVE-0-2026-59969)

Vulnerability from cvelistv5 – Published: 2026-09-16 09:27 – Updated: 2026-09-17 19:17

Title

Apache ZooKeeper: Improper validation of certificate with host mismatch in FIPS mode

Summary

Severity

7.5 (High)


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

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-09-17 19:16 UTC

CWE

CWE-297 - Improper Validation of Certificate with Host Mismatch

Assigner

apache mitre root

References

2 references

URL	Tags
https://lists.apache.org/thread/qf9kwsgtgbgtvwls6…	vendor-advisory
http://www.openwall.com/lists/oss-security/2026/09/15/4

Impacted products

1 product

Vendor	Product	Version
Apache Software Foundation	Apache ZooKeeper	Affected: 3.9.0 , ≤ 3.9.5 (maven) Affected: 3.8.0 , ≤ 3.8.6 (maven)

Credits

Erichen <chenyoulong20g@ict.ac.cn>

Show details on NVD website

JSON

To clipboard

{
  "containers": {
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      {
        "providerMetadata": {
          "dateUpdated": "2026-09-16T10:11:44.041Z",
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        "references": [
          {
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          }
        ],
        "title": "CVE Program Container"
      },
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        "metrics": [
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              "baseScore": 7.5,
              "baseSeverity": "HIGH",
              "confidentialityImpact": "NONE",
              "integrityImpact": "HIGH",
              "privilegesRequired": "NONE",
              "scope": "UNCHANGED",
              "userInteraction": "NONE",
              "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N",
              "version": "3.1"
            }
          },
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            "other": {
              "content": {
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                  },
                  {
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                  },
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                "role": "CISA Coordinator",
                "timestamp": "2026-09-17T19:16:38.006304Z",
                "version": "2.0.3"
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        "providerMetadata": {
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          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
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          "defaultStatus": "unaffected",
          "packageName": "org.apache.zookeeper:zookeeper",
          "packageURL": "pkg:maven/org.apache.zookeeper/zookeeper",
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              "status": "affected",
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            },
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      "credits": [
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          "type": "reporter",
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        }
      ],
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      "metrics": [
        {
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              "text": "important"
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          "scenarios": [
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      "source": {
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    "datePublished": "2026-09-16T09:27:00.726Z",
    "dateReserved": "2026-07-07T18:50:40.959Z",
    "dateUpdated": "2026-09-17T19:17:01.444Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
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}

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.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

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