CVE-2026-102139

Status: Awaiting AnalysisMedium (6.5)—

An authorization check in the large file exchange feature of Kiteworks Email Protection Gateway did not correctly establish that the requesting user was a party to the package being requested. An authenticated user of that optional feature could read the subject, message body, and attachments of packages they neither sent nor received.

CVSS

Version: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Base score: 6.5

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 0.35%
Percentile among all scored CVEs: 27
Score date: 10/1/2026

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.

Kiteworks — Email Protection Gateway^AI

CWEs

CWE-639, CWE-863

References

Raw JSON (NVD)

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{
  "id": "CVE-2026-102139",
  "cveTags": [],
  "metrics": {
    "cvssMetricV31": [
      {
        "type": "Secondary",
        "source": "9119a7d8-5eab-497f-8521-727c672e3725",
        "cvssData": {
          "scope": "UNCHANGED",
          "version": "3.1",
          "baseScore": 6.5,
          "attackVector": "NETWORK",
          "baseSeverity": "MEDIUM",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N",
          "integrityImpact": "NONE",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "NONE",
          "privilegesRequired": "LOW",
          "confidentialityImpact": "HIGH"
        },
        "impactScore": 3.6,
        "exploitabilityScore": 2.8
      }
    ]
  },
  "affected": [
    {
      "source": "9119a7d8-5eab-497f-8521-727c672e3725",
      "affectedData": [
        {
          "vendor": "Kiteworks",
          "product": "Email Protection Gateway",
          "versions": [
            {
              "status": "affected",
              "version": "0",
              "lessThan": "9.5.1",
              "versionType": "custom"
            },
            {
              "status": "unaffected",
              "version": "9.5.1"
            }
          ],
          "defaultStatus": "unknown"
        }
      ]
    }
  ],
  "published": "2026-09-30T21:17:02.663",
  "references": [
    {
      "url": "https://github.com/kiteworks/security-advisories/security/advisories/GHSA-fp46-xhg8-vpgm",
      "source": "9119a7d8-5eab-497f-8521-727c672e3725"
    },
    {
      "url": "https://raw.githubusercontent.com/cisagov/CSAF/develop/csaf_files/VA/white/2026/va-26-274-01.json",
      "source": "9119a7d8-5eab-497f-8521-727c672e3725"
    }
  ],
  "vulnStatus": "Awaiting Analysis",
  "weaknesses": [
    {
      "type": "Secondary",
      "source": "9119a7d8-5eab-497f-8521-727c672e3725",
      "description": [
        {
          "lang": "en",
          "value": "CWE-639"
        },
        {
          "lang": "en",
          "value": "CWE-863"
        }
      ]
    }
  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "An authorization check in the large file exchange feature of Kiteworks Email Protection Gateway did not correctly establish that the requesting user was a party to the package being requested. An authenticated user of that optional feature could read the subject, message body, and attachments of packages they neither sent nor received."
    }
  ],
  "lastModified": "2026-10-01T02:17:43.350",
  "sourceIdentifier": "9119a7d8-5eab-497f-8521-727c672e3725"
}