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GHSA-FJ5V-QH2P-6V8F

Vulnerability from github – Published: 2026-09-30 12:35 – Updated: 2026-09-30 12:35

Details

Using a very small "block size" (for instance 256, which is the minimum) on a huge file generates many (file size / block size) hashes. The resulting SFTP reply message was accumulated fully in memory server-side, which could, with a suitably large (possibly sparse) file exhaust the server-side memory, taking down the server.

Users are recommended to upgrade to version 2.20.0 or 3.0.0-M6, which fix this issue by imposing a maximum limit on the size of the reply. Many SFTP implementations have a general limit on the size of SFTP messages anyway; typically 256kB as in OpenSSH or also in Apache MINA SSHD.

Severity

6.5 (Medium)


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

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{
  "affected": [],
  "aliases": [
    "CVE-2026-94029"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-770"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-09-30T10:17:18Z",
    "severity": "MODERATE"
  },
  "details": "Server-side memory exhaustion in Apache MINA SSHD 1.0.0 to 2.19.0 and 3.0.0-M1 to 3.0.0-M5, component sshd-sftp, in the SFTP v6 check-file-name/check-file-handle extension.\u00a0Apache MINA SSHD is a Java library for client-side and server-side SSH.\n\n\n\n\nUsing a very small \"block size\" (for instance 256, which is the minimum) on a huge file generates many (file size / block size) hashes. The resulting SFTP reply message was accumulated fully in memory server-side, which could, with a suitably large\u00a0(possibly sparse)\u00a0file exhaust the server-side memory, taking down the server.\n\n\n\n\nUsers are recommended to upgrade to version 2.20.0 or 3.0.0-M6, which fix this issue by imposing a maximum limit on the size of the reply. Many SFTP implementations have a general limit on the size of SFTP messages anyway; typically 256kB as in OpenSSH or also in Apache MINA SSHD.",
  "id": "GHSA-fj5v-qh2p-6v8f",
  "modified": "2026-09-30T12:35:16Z",
  "published": "2026-09-30T12:35:16Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-94029"
    },
    {
      "type": "WEB",
      "url": "https://lists.apache.org/thread.html/ytbl4rwby62xl7llm3wp7k975wwdx99t"
    },
    {
      "type": "WEB",
      "url": "http://www.openwall.com/lists/oss-security/2026/09/29/37"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-94029 (GCVE-0-2026-94029)

Vulnerability from cvelistv5 – Published: 2026-09-30 09:35 – Updated: 2026-09-30 19:42

Title

Apache MINA SSHD: Memory exhaustion in SFTP v6 check-file-name/check-file-handle extension

Summary

Server-side memory exhaustion in Apache MINA SSHD 1.0.0 to 2.19.0 and 3.0.0-M1 to 3.0.0-M5, component sshd-sftp, in the SFTP v6 check-file-name/check-file-handle extension. Apache MINA SSHD is a Java library for client-side and server-side SSH. Using a very small "block size" (for instance 256, which is the minimum) on a huge file generates many (file size / block size) hashes. The resulting SFTP reply message was accumulated fully in memory server-side, which could, with a suitably large (possibly sparse) file exhaust the server-side memory, taking down the server. Users are recommended to upgrade to version 2.20.0 or 3.0.0-M6, which fix this issue by imposing a maximum limit on the size of the reply. Many SFTP implementations have a general limit on the size of SFTP messages anyway; typically 256kB as in OpenSSH or also in Apache MINA SSHD.

Severity

6.5 (Medium)


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

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-09-30 19:42 UTC

CWE

CWE-770 - Allocation of resources without limits or throttling

Assigner

apache mitre root Scorecard

References

2 references

URL	Tags
https://lists.apache.org/thread.html/ytbl4rwby62x…	vendor-advisory
http://www.openwall.com/lists/oss-security/2026/0…

Impacted products

1 product

Vendor	Product	Version
Apache Software Foundation	Apache MINA SSHD	Affected: 1.0.0 , < 2.20.0 (maven) Affected: 3.0.0-M1 , < 3.0.0-M6 (maven)

Credits

Ho1aAs <xxy010605@gmail.com>

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "providerMetadata": {
          "dateUpdated": "2026-09-30T10:14:18.127Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
          "shortName": "CVE"
        },
        "references": [
          {
            "url": "http://www.openwall.com/lists/oss-security/2026/09/29/37"
          }
        ],
        "title": "CVE Program Container"
      },
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-94029",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-09-30T19:42:43.742304Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-09-30T19:42:56.102Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "collectionURL": "https://repo.maven.apache.org/maven2",
          "defaultStatus": "unaffected",
          "packageName": "org.apache.sshd:sshd-sftp",
          "packageURL": "pkg:maven/org.apache.sshd/sshd-sftp",
          "product": "Apache MINA SSHD",
          "vendor": "Apache Software Foundation",
          "versions": [
            {
              "lessThan": "2.20.0",
              "status": "affected",
              "version": "1.0.0",
              "versionType": "maven"
            },
            {
              "lessThan": "3.0.0-M6",
              "status": "affected",
              "version": "3.0.0-M1",
              "versionType": "maven"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "Ho1aAs \u003cxxy010605@gmail.com\u003e"
        }
      ],
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            "userInteraction": "NONE",
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              "type": "CWE"
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      "providerMetadata": {
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      "references": [
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          "url": "https://lists.apache.org/thread.html/ytbl4rwby62xl7llm3wp7k975wwdx99t"
        }
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      "source": {
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    "datePublished": "2026-09-30T09:35:51.711Z",
    "dateReserved": "2026-09-19T17:17:00.525Z",
    "dateUpdated": "2026-09-30T19:42:56.102Z",
    "state": "PUBLISHED"
  },
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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.

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.

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GHSA-FJ5V-QH2P-6V8F

CVE-2026-94029 (GCVE-0-2026-94029)

Tags

Sightings

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