Vulnerability-Lookup

GHSA-36R8-H3X6-X34C

Vulnerability from github – Published: 2026-08-26 18:31 – Updated: 2026-08-26 18:31

Details

Netmaker disables certificate verification on the connection to the configured mail server. The sender in pro/email/smtp.go assigns a TLS configuration whose skip-verify field is set to true unconditionally, directly beneath a comment stating that the setting should be false in production. No configuration value governs it and no code path restores verification, so the client accepts any certificate the mail server presents, including one an interposing party supplies. Mail that Netmaker sends over that connection includes password-reset messages carrying single-use tokens and user invitations carrying enrolment links, so a party positioned on the path between the server and its mail relay can read those messages in transit and use a captured reset token before the intended recipient does. The setting is absent from the development branch but present in the latest release.

Severity

6.5 (Medium)


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

8.3 (High)


                  
                    CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N

Show details on source website

JSON

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{
  "affected": [],
  "aliases": [
    "CVE-2026-81034"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-295"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-08-26T16:16:46Z",
    "severity": "HIGH"
  },
  "details": "Netmaker disables certificate verification on the connection to the configured mail server. The sender in pro/email/smtp.go assigns a TLS configuration whose skip-verify field is set to true unconditionally, directly beneath a comment stating that the setting should be false in production. No configuration value governs it and no code path restores verification, so the client accepts any certificate the mail server presents, including one an interposing party supplies. Mail that Netmaker sends over that connection includes password-reset messages carrying single-use tokens and user invitations carrying enrolment links, so a party positioned on the path between the server and its mail relay can read those messages in transit and use a captured reset token before the intended recipient does. The setting is absent from the development branch but present in the latest release.",
  "id": "GHSA-36r8-h3x6-x34c",
  "modified": "2026-08-26T18:31:56Z",
  "published": "2026-08-26T18:31:56Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-81034"
    },
    {
      "type": "WEB",
      "url": "https://github.com/gravitl/netmaker/issues/4062"
    },
    {
      "type": "WEB",
      "url": "https://github.com/gravitl/netmaker"
    },
    {
      "type": "WEB",
      "url": "https://github.com/gravitl/netmaker/blob/v1.6.0/pro/email/smtp.go"
    },
    {
      "type": "WEB",
      "url": "https://www.vulncheck.com/advisories/netmaker-through-1.6.0-improper-certificate-validation-in-smtp-client"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
      "type": "CVSS_V4"
    }
  ]
}

CVE-2026-81034 (GCVE-0-2026-81034)

Vulnerability from cvelistv5 – Published: 2026-08-26 15:45 – Updated: 2026-08-26 18:31

Title

Netmaker through 1.6.0 Improper Certificate Validation in SMTP Client

Summary

Severity

8.3 (High)


                        
                          CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N

6.5 (Medium)


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

SSVC

Exploitation: poc Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-08-26 18:30 UTC

CWE

CWE-295 - Improper Certificate Validation

Assigner

VulnCheck mitre root

References

4 references

URL	Tags
https://github.com/gravitl/netmaker	product
https://github.com/gravitl/netmaker/issues/4062	issue-tracking
https://github.com/gravitl/netmaker/blob/v1.6.0/p…	technical-description
https://www.vulncheck.com/advisories/netmaker-thr…	third-party-advisory

Impacted products

1 product

Vendor	Product	Version
gravitl	netmaker	Affected: 0 , ≤ 1.6.0 (semver) cpe:2.3:a:netmaker:netmaker::::::::

Date Public

2026-08-26 00:00

Credits

George Chen

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-81034",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-08-26T18:30:06.108580Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-08-26T18:31:47.883Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "references": [
          {
            "tags": [
              "exploit"
            ],
            "url": "https://github.com/gravitl/netmaker/issues/4062"
          }
        ],
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "collectionURL": "https://github.com/gravitl/netmaker",
          "defaultStatus": "unaffected",
          "packageURL": "pkg:github/gravitl/netmaker",
          "product": "netmaker",
          "repo": "https://github.com/gravitl/netmaker",
          "vendor": "gravitl",
          "versions": [
            {
              "lessThanOrEqual": "1.6.0",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:a:netmaker:netmaker:*:*:*:*:*:*:*:*",
                  "versionEndIncluding": "1.6.0",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "George Chen"
        }
      ],
      "datePublic": "2026-08-26T00:00:00.000Z",
      "descriptions": [
        {
          "lang": "en",
          "value": "Netmaker disables certificate verification on the connection to the configured mail server. The sender in pro/email/smtp.go assigns a TLS configuration whose skip-verify field is set to true unconditionally, directly beneath a comment stating that the setting should be false in production. No configuration value governs it and no code path restores verification, so the client accepts any certificate the mail server presents, including one an interposing party supplies. Mail that Netmaker sends over that connection includes password-reset messages carrying single-use tokens and user invitations carrying enrolment links, so a party positioned on the path between the server and its mail relay can read those messages in transit and use a captured reset token before the intended recipient does. The setting is absent from the development branch but present in the latest release."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "Automatable": "NOT_DEFINED",
            "Recovery": "NOT_DEFINED",
            "Safety": "NOT_DEFINED",
            "attackComplexity": "LOW",
            "attackRequirements": "PRESENT",
            "attackVector": "NETWORK",
            "baseScore": 8.3,
            "baseSeverity": "HIGH",
            "exploitMaturity": "NOT_DEFINED",
            "privilegesRequired": "NONE",
            "providerUrgency": "NOT_DEFINED",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "NONE",
            "valueDensity": "NOT_DEFINED",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "NONE",
            "vulnConfidentialityImpact": "HIGH",
            "vulnIntegrityImpact": "LOW",
            "vulnerabilityResponseEffort": "NOT_DEFINED"
          },
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
          ]
        },
        {
          "cvssV3_1": {
            "attackComplexity": "HIGH",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 6.5,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "LOW",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N",
            "version": "3.1"
          },
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
          ]
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-295",
              "description": "Improper Certificate Validation",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-26T15:45:01.529Z",
        "orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
        "shortName": "VulnCheck"
      },
      "references": [
        {
          "tags": [
            "product"
          ],
          "url": "https://github.com/gravitl/netmaker"
        },
        {
          "tags": [
            "issue-tracking"
          ],
          "url": "https://github.com/gravitl/netmaker/issues/4062"
        },
        {
          "tags": [
            "technical-description"
          ],
          "url": "https://github.com/gravitl/netmaker/blob/v1.6.0/pro/email/smtp.go"
        },
        {
          "name": "VulnCheck Advisory: Netmaker through 1.6.0 Improper Certificate Validation in SMTP Client",
          "tags": [
            "third-party-advisory"
          ],
          "url": "https://www.vulncheck.com/advisories/netmaker-through-1.6.0-improper-certificate-validation-in-smtp-client"
        }
      ],
      "source": {
        "discovery": "UNKNOWN"
      },
      "title": "Netmaker through 1.6.0 Improper Certificate Validation in SMTP Client",
      "x_generator": {
        "engine": "vulncheck-endgame"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
    "assignerShortName": "VulnCheck",
    "cveId": "CVE-2026-81034",
    "datePublished": "2026-08-26T15:45:01.529Z",
    "dateReserved": "2026-08-26T15:23:07.420Z",
    "dateUpdated": "2026-08-26T18:31:47.883Z",
    "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

GHSA-36R8-H3X6-X34C

CVE-2026-81034 (GCVE-0-2026-81034)

Tags

Sightings

Nomenclature