Vulnerability-Lookup

CVE-2026-86121 (GCVE-0-2026-86121)

Vulnerability from cvelistv5 – Published: 2026-09-05 09:59 – Updated: 2026-09-05 09:59

Title

Cua computer-server before 0.3.42 Unauthenticated RCE via Desktop Control

Summary

Cua computer-server versions before 0.3.42 skip authentication when the CONTAINER_NAME environment variable is unset and bind to all interfaces by default, allowing unauthenticated attackers to execute arbitrary commands. Attackers can reach TCP port 8000 to run shell commands via the run_command endpoint, read and write arbitrary files through file operation endpoints, and access interactive PTY shells without authentication.

Severity

9.3 (Critical)


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

9.8 (Critical)


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

CWE

CWE-306 - Missing Authentication for Critical Function

Assigner

VulnCheck mitre root

References

6 references

URL	Tags
https://github.com/trycua/cua/issues/1892	issue-tracking
https://github.com/trycua/cua/blob/10a2e71792db/l…	technical-description
https://github.com/trycua/cua/blob/10a2e71792db/l…	technical-description
https://github.com/trycua/cua/commit/59cf25c0ec54	patch
https://github.com/trycua/cua	product
https://www.vulncheck.com/advisories/cua-computer…	third-party-advisory

Impacted products

1 product

Vendor	Product	Version	CPE status
trycua	cua-computer-server	Affected: 0 , < 0.3.42 (semver)	guessed

Date Public

2026-06-13 00:00

Credits

George Chen

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "packageURL": "pkg:pypi/cua-computer-server",
          "product": "cua-computer-server",
          "repo": "https://github.com/trycua/cua",
          "vendor": "trycua",
          "versions": [
            {
              "lessThan": "0.3.42",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "reporter",
          "value": "George Chen"
        }
      ],
      "datePublic": "2026-06-13T00:00:00.000Z",
      "descriptions": [
        {
          "lang": "en",
          "value": "Cua computer-server versions before 0.3.42 skip authentication when the CONTAINER_NAME environment variable is unset and bind to all interfaces by default, allowing unauthenticated attackers to execute arbitrary commands. Attackers can reach TCP port 8000 to run shell commands via the run_command endpoint, read and write arbitrary files through file operation endpoints, and access interactive PTY shells without authentication."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "attackVector": "NETWORK",
            "baseScore": 9.3,
            "baseSeverity": "CRITICAL",
            "privilegesRequired": "NONE",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "NONE",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "HIGH",
            "vulnConfidentialityImpact": "HIGH",
            "vulnIntegrityImpact": "HIGH"
          },
          "format": "CVSS"
        },
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 9.8,
            "baseSeverity": "CRITICAL",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "format": "CVSS"
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-306",
              "description": "Missing Authentication for Critical Function",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-09-05T09:59:10.093Z",
        "orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
        "shortName": "VulnCheck"
      },
      "references": [
        {
          "name": "GitHub Issue #1892",
          "tags": [
            "issue-tracking"
          ],
          "url": "https://github.com/trycua/cua/issues/1892"
        },
        {
          "name": "Server.auth allow-all when CONTAINER_NAME is unset",
          "tags": [
            "technical-description"
          ],
          "url": "https://github.com/trycua/cua/blob/10a2e71792db/libs/python/computer-server/computer_server/main.py"
        },
        {
          "name": "CLI --host default of 0.0.0.0",
          "tags": [
            "technical-description"
          ],
          "url": "https://github.com/trycua/cua/blob/10a2e71792db/libs/python/computer-server/computer_server/cli.py"
        },
        {
          "name": "Bind default changed to 127.0.0.1",
          "tags": [
            "patch"
          ],
          "url": "https://github.com/trycua/cua/commit/59cf25c0ec54"
        },
        {
          "tags": [
            "product"
          ],
          "url": "https://github.com/trycua/cua"
        },
        {
          "name": "VulnCheck Advisory: Cua computer-server before 0.3.42 Unauthenticated RCE via Desktop Control",
          "tags": [
            "third-party-advisory"
          ],
          "url": "https://www.vulncheck.com/advisories/cua-computer-server-before-0.3.42-unauthenticated-rce-via-desktop-control"
        }
      ],
      "title": "Cua computer-server before 0.3.42 Unauthenticated RCE via Desktop Control",
      "x_generator": {
        "engine": "vulncheck-endgame"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
    "assignerShortName": "VulnCheck",
    "cveId": "CVE-2026-86121",
    "datePublished": "2026-09-05T09:59:10.093Z",
    "dateReserved": "2026-09-05T01:59:22.753Z",
    "dateUpdated": "2026-09-05T09:59:10.093Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-86121",
      "date": "2026-09-06",
      "epss": "0.00592",
      "percentile": "0.46144"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2026-86121\",\"sourceIdentifier\":\"disclosure@vulncheck.com\",\"published\":\"2026-09-05T10:16:43.463\",\"lastModified\":\"2026-09-05T10:16:43.463\",\"vulnStatus\":\"Received\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"Cua computer-server versions before 0.3.42 skip authentication when the CONTAINER_NAME environment variable is unset and bind to all interfaces by default, allowing unauthenticated attackers to execute arbitrary commands. Attackers can reach TCP port 8000 to run shell commands via the run_command endpoint, read and write arbitrary files through file operation endpoints, and access interactive PTY shells without authentication.\"}],\"affected\":[{\"source\":\"disclosure@vulncheck.com\",\"affectedData\":[{\"vendor\":\"trycua\",\"product\":\"cua-computer-server\",\"defaultStatus\":\"unaffected\",\"repo\":\"https://github.com/trycua/cua\",\"packageURL\":\"pkg:pypi/cua-computer-server\",\"versions\":[{\"version\":\"0\",\"lessThan\":\"0.3.42\",\"versionType\":\"semver\",\"status\":\"affected\"}]}]}],\"metrics\":{\"cvssMetricV40\":[{\"source\":\"disclosure@vulncheck.com\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"4.0\",\"vectorString\":\"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/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\",\"baseScore\":9.3,\"baseSeverity\":\"CRITICAL\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"attackRequirements\":\"NONE\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"NONE\",\"vulnConfidentialityImpact\":\"HIGH\",\"vulnIntegrityImpact\":\"HIGH\",\"vulnAvailabilityImpact\":\"HIGH\",\"subConfidentialityImpact\":\"NONE\",\"subIntegrityImpact\":\"NONE\",\"subAvailabilityImpact\":\"NONE\",\"exploitMaturity\":\"NOT_DEFINED\",\"confidentialityRequirement\":\"NOT_DEFINED\",\"integrityRequirement\":\"NOT_DEFINED\",\"availabilityRequirement\":\"NOT_DEFINED\",\"modifiedAttackVector\":\"NOT_DEFINED\",\"modifiedAttackComplexity\":\"NOT_DEFINED\",\"modifiedAttackRequirements\":\"NOT_DEFINED\",\"modifiedPrivilegesRequired\":\"NOT_DEFINED\",\"modifiedUserInteraction\":\"NOT_DEFINED\",\"modifiedVulnConfidentialityImpact\":\"NOT_DEFINED\",\"modifiedVulnIntegrityImpact\":\"NOT_DEFINED\",\"modifiedVulnAvailabilityImpact\":\"NOT_DEFINED\",\"modifiedSubConfidentialityImpact\":\"NOT_DEFINED\",\"modifiedSubIntegrityImpact\":\"NOT_DEFINED\",\"modifiedSubAvailabilityImpact\":\"NOT_DEFINED\",\"Safety\":\"NOT_DEFINED\",\"Automatable\":\"NOT_DEFINED\",\"Recovery\":\"NOT_DEFINED\",\"valueDensity\":\"NOT_DEFINED\",\"vulnerabilityResponseEffort\":\"NOT_DEFINED\",\"providerUrgency\":\"NOT_DEFINED\"}}],\"cvssMetricV31\":[{\"source\":\"disclosure@vulncheck.com\",\"type\":\"Primary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H\",\"baseScore\":9.8,\"baseSeverity\":\"CRITICAL\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"HIGH\",\"integrityImpact\":\"HIGH\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":3.9,\"impactScore\":5.9}]},\"weaknesses\":[{\"source\":\"disclosure@vulncheck.com\",\"type\":\"Primary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-306\"}]}],\"references\":[{\"url\":\"https://github.com/trycua/cua\",\"source\":\"disclosure@vulncheck.com\"},{\"url\":\"https://github.com/trycua/cua/blob/10a2e71792db/libs/python/computer-server/computer_server/cli.py\",\"source\":\"disclosure@vulncheck.com\"},{\"url\":\"https://github.com/trycua/cua/blob/10a2e71792db/libs/python/computer-server/computer_server/main.py\",\"source\":\"disclosure@vulncheck.com\"},{\"url\":\"https://github.com/trycua/cua/commit/59cf25c0ec54\",\"source\":\"disclosure@vulncheck.com\"},{\"url\":\"https://github.com/trycua/cua/issues/1892\",\"source\":\"disclosure@vulncheck.com\"},{\"url\":\"https://www.vulncheck.com/advisories/cua-computer-server-before-0.3.42-unauthenticated-rce-via-desktop-control\",\"source\":\"disclosure@vulncheck.com\"}]}}"
  }
}

FKIE_CVE-2026-86121

Vulnerability from fkie_nvd - Published: 2026-09-05 10:16 - Updated: 2026-09-05 10:16

Severity

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

Summary

References

	URL	Tags
	disclosure@vulncheck.com	https://github.com/trycua/cua
	disclosure@vulncheck.com	https://github.com/trycua/cua/blob/10a2e71792db/libs/python/computer-server/computer_server/cli.py
	disclosure@vulncheck.com	https://github.com/trycua/cua/blob/10a2e71792db/libs/python/computer-server/computer_server/main.py
	disclosure@vulncheck.com	https://github.com/trycua/cua/commit/59cf25c0ec54
	disclosure@vulncheck.com	https://github.com/trycua/cua/issues/1892
	disclosure@vulncheck.com	https://www.vulncheck.com/advisories/cua-computer-server-before-0.3.42-unauthenticated-rce-via-desktop-control

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "packageURL": "pkg:pypi/cua-computer-server",
          "product": "cua-computer-server",
          "repo": "https://github.com/trycua/cua",
          "vendor": "trycua",
          "versions": [
            {
              "lessThan": "0.3.42",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "source": "disclosure@vulncheck.com"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Cua computer-server versions before 0.3.42 skip authentication when the CONTAINER_NAME environment variable is unset and bind to all interfaces by default, allowing unauthenticated attackers to execute arbitrary commands. Attackers can reach TCP port 8000 to run shell commands via the run_command endpoint, read and write arbitrary files through file operation endpoints, and access interactive PTY shells without authentication."
    }
  ],
  "id": "CVE-2026-86121",
  "lastModified": "2026-09-05T10:16:43.463",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 9.8,
          "baseSeverity": "CRITICAL",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 5.9,
        "source": "disclosure@vulncheck.com",
        "type": "Primary"
      }
    ],
    "cvssMetricV40": [
      {
        "cvssData": {
          "Automatable": "NOT_DEFINED",
          "Recovery": "NOT_DEFINED",
          "Safety": "NOT_DEFINED",
          "attackComplexity": "LOW",
          "attackRequirements": "NONE",
          "attackVector": "NETWORK",
          "availabilityRequirement": "NOT_DEFINED",
          "baseScore": 9.3,
          "baseSeverity": "CRITICAL",
          "confidentialityRequirement": "NOT_DEFINED",
          "exploitMaturity": "NOT_DEFINED",
          "integrityRequirement": "NOT_DEFINED",
          "modifiedAttackComplexity": "NOT_DEFINED",
          "modifiedAttackRequirements": "NOT_DEFINED",
          "modifiedAttackVector": "NOT_DEFINED",
          "modifiedPrivilegesRequired": "NOT_DEFINED",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
          "modifiedSubConfidentialityImpact": "NOT_DEFINED",
          "modifiedSubIntegrityImpact": "NOT_DEFINED",
          "modifiedUserInteraction": "NOT_DEFINED",
          "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
          "modifiedVulnConfidentialityImpact": "NOT_DEFINED",
          "modifiedVulnIntegrityImpact": "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:N/PR:N/UI:N/VC:H/VI:H/VA:H/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",
          "version": "4.0",
          "vulnAvailabilityImpact": "HIGH",
          "vulnConfidentialityImpact": "HIGH",
          "vulnIntegrityImpact": "HIGH",
          "vulnerabilityResponseEffort": "NOT_DEFINED"
        },
        "source": "disclosure@vulncheck.com",
        "type": "Secondary"
      }
    ]
  },
  "published": "2026-09-05T10:16:43.463",
  "references": [
    {
      "source": "disclosure@vulncheck.com",
      "url": "https://github.com/trycua/cua"
    },
    {
      "source": "disclosure@vulncheck.com",
      "url": "https://github.com/trycua/cua/blob/10a2e71792db/libs/python/computer-server/computer_server/cli.py"
    },
    {
      "source": "disclosure@vulncheck.com",
      "url": "https://github.com/trycua/cua/blob/10a2e71792db/libs/python/computer-server/computer_server/main.py"
    },
    {
      "source": "disclosure@vulncheck.com",
      "url": "https://github.com/trycua/cua/commit/59cf25c0ec54"
    },
    {
      "source": "disclosure@vulncheck.com",
      "url": "https://github.com/trycua/cua/issues/1892"
    },
    {
      "source": "disclosure@vulncheck.com",
      "url": "https://www.vulncheck.com/advisories/cua-computer-server-before-0.3.42-unauthenticated-rce-via-desktop-control"
    }
  ],
  "sourceIdentifier": "disclosure@vulncheck.com",
  "vulnStatus": "Received",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-306"
        }
      ],
      "source": "disclosure@vulncheck.com",
      "type": "Primary"
    }
  ]
}

GHSA-PCCW-H89V-H9CJ

Vulnerability from github – Published: 2026-09-05 12:31 – Updated: 2026-09-05 12:31

Details

Severity

9.8 (Critical)


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

9.3 (Critical)


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

Show details on source website

JSON

To clipboard

{
  "affected": [],
  "aliases": [
    "CVE-2026-86121"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-306"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-09-05T10:16:43Z",
    "severity": "CRITICAL"
  },
  "details": "Cua computer-server versions before 0.3.42 skip authentication when the CONTAINER_NAME environment variable is unset and bind to all interfaces by default, allowing unauthenticated attackers to execute arbitrary commands. Attackers can reach TCP port 8000 to run shell commands via the run_command endpoint, read and write arbitrary files through file operation endpoints, and access interactive PTY shells without authentication.",
  "id": "GHSA-pccw-h89v-h9cj",
  "modified": "2026-09-05T12:31:26Z",
  "published": "2026-09-05T12:31:26Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-86121"
    },
    {
      "type": "WEB",
      "url": "https://github.com/trycua/cua/issues/1892"
    },
    {
      "type": "WEB",
      "url": "https://github.com/trycua/cua/commit/59cf25c0ec54"
    },
    {
      "type": "WEB",
      "url": "https://github.com/trycua/cua"
    },
    {
      "type": "WEB",
      "url": "https://github.com/trycua/cua/blob/10a2e71792db/libs/python/computer-server/computer_server/cli.py"
    },
    {
      "type": "WEB",
      "url": "https://github.com/trycua/cua/blob/10a2e71792db/libs/python/computer-server/computer_server/main.py"
    },
    {
      "type": "WEB",
      "url": "https://www.vulncheck.com/advisories/cua-computer-server-before-0.3.42-unauthenticated-rce-via-desktop-control"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/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"
    }
  ]
}

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

CVE-2026-86121 (GCVE-0-2026-86121)

FKIE_CVE-2026-86121

GHSA-PCCW-H89V-H9CJ

Tags

Sightings

Nomenclature