Vulnerability-Lookup

FKIE_CVE-2026-39031

Vulnerability from fkie_nvd - Published: 2026-06-26 21:16 - Updated: 2026-06-29 19:27

Severity

5.5 (Medium) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

Summary

Lansweeper lsrunase 2.0 and lsencrypt 2.0 use RC4 encryption with a hardcoded 142-byte static key array to encrypt credentials. An 8-character prefix is stored in cleartext alongside the ciphertext. This allows an attacker with local access to recover any encrypted password to plaintext using a single SHA-1 hash and RC4 decryption operation, with no brute force required.

References

	URL	Tags
	cve@mitre.org	https://github.com/user6400/cve-2026-39031-lansweeper-lsrunase2-lsencrypt2
	cve@mitre.org	https://usermode.net/cve/lansweeper_lsrunase2_lsencrypt2_cve.pdf
	134c704f-9b21-4f2e-91b3-4a467353bcc0	https://github.com/user6400/cve-2026-39031-lansweeper-lsrunase2-lsencrypt2
	134c704f-9b21-4f2e-91b3-4a467353bcc0	https://usermode.net/cve/lansweeper_lsrunase2_lsencrypt2_cve.pdf

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "n/a",
          "vendor": "n/a",
          "versions": [
            {
              "status": "affected",
              "version": "n/a"
            }
          ]
        }
      ],
      "source": "cve@mitre.org"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Lansweeper lsrunase 2.0 and lsencrypt 2.0 use RC4 encryption with a hardcoded 142-byte static key array to encrypt credentials. An 8-character prefix is stored in cleartext alongside the ciphertext. This allows an attacker with local access to recover any encrypted password to plaintext using a single SHA-1 hash and RC4 decryption operation, with no brute force required."
    }
  ],
  "id": "CVE-2026-39031",
  "lastModified": "2026-06-29T19:27:07.477",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "LOCAL",
          "availabilityImpact": "NONE",
          "baseScore": 5.5,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "NONE",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 3.6,
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-39031",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-06-29T13:37:09.839096Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-06-26T21:16:33.600",
  "references": [
    {
      "source": "cve@mitre.org",
      "url": "https://github.com/user6400/cve-2026-39031-lansweeper-lsrunase2-lsencrypt2"
    },
    {
      "source": "cve@mitre.org",
      "url": "https://usermode.net/cve/lansweeper_lsrunase2_lsencrypt2_cve.pdf"
    },
    {
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "url": "https://github.com/user6400/cve-2026-39031-lansweeper-lsrunase2-lsencrypt2"
    },
    {
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "url": "https://usermode.net/cve/lansweeper_lsrunase2_lsencrypt2_cve.pdf"
    }
  ],
  "sourceIdentifier": "cve@mitre.org",
  "vulnStatus": "Deferred",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-321"
        }
      ],
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "type": "Secondary"
    }
  ]
}

CVE-2026-39031 (GCVE-0-2026-39031)

Vulnerability from cvelistv5 – Published: 2026-06-26 00:00 – Updated: 2026-06-29 13:37

Summary

Severity

5.5 (Medium)


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

SSVC

Exploitation: poc Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-06-29 13:37 UTC

CWE

n/a
CWE-321 - Use of Hard-coded Cryptographic Key

Assigner

mitre mitre root

References

2 references

URL	Tags
https://usermode.net/cve/lansweeper_lsrunase2_lse…
https://github.com/user6400/cve-2026-39031-lanswe…

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "cvssV3_1": {
              "attackComplexity": "LOW",
              "attackVector": "LOCAL",
              "availabilityImpact": "NONE",
              "baseScore": 5.5,
              "baseSeverity": "MEDIUM",
              "confidentialityImpact": "HIGH",
              "integrityImpact": "NONE",
              "privilegesRequired": "LOW",
              "scope": "UNCHANGED",
              "userInteraction": "NONE",
              "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N",
              "version": "3.1"
            }
          },
          {
            "other": {
              "content": {
                "id": "CVE-2026-39031",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-06-29T13:37:09.839096Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "problemTypes": [
          {
            "descriptions": [
              {
                "cweId": "CWE-321",
                "description": "CWE-321 Use of Hard-coded Cryptographic Key",
                "lang": "en",
                "type": "CWE"
              }
            ]
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-06-29T13:37:17.723Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "references": [
          {
            "tags": [
              "exploit"
            ],
            "url": "https://usermode.net/cve/lansweeper_lsrunase2_lsencrypt2_cve.pdf"
          },
          {
            "tags": [
              "exploit"
            ],
            "url": "https://github.com/user6400/cve-2026-39031-lansweeper-lsrunase2-lsencrypt2"
          }
        ],
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "n/a",
          "vendor": "n/a",
          "versions": [
            {
              "status": "affected",
              "version": "n/a"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Lansweeper lsrunase 2.0 and lsencrypt 2.0 use RC4 encryption with a hardcoded 142-byte static key array to encrypt credentials. An 8-character prefix is stored in cleartext alongside the ciphertext. This allows an attacker with local access to recover any encrypted password to plaintext using a single SHA-1 hash and RC4 decryption operation, with no brute force required."
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "description": "n/a",
              "lang": "en",
              "type": "text"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-06-26T20:43:01.496Z",
        "orgId": "8254265b-2729-46b6-b9e3-3dfca2d5bfca",
        "shortName": "mitre"
      },
      "references": [
        {
          "url": "https://usermode.net/cve/lansweeper_lsrunase2_lsencrypt2_cve.pdf"
        },
        {
          "url": "https://github.com/user6400/cve-2026-39031-lansweeper-lsrunase2-lsencrypt2"
        }
      ]
    }
  },
  "cveMetadata": {
    "assignerOrgId": "8254265b-2729-46b6-b9e3-3dfca2d5bfca",
    "assignerShortName": "mitre",
    "cveId": "CVE-2026-39031",
    "datePublished": "2026-06-26T00:00:00.000Z",
    "dateReserved": "2026-04-06T00:00:00.000Z",
    "dateUpdated": "2026-06-29T13:37:17.723Z",
    "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.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.