Vulnerability-Lookup

CVE-2026-55545 (GCVE-0-2026-55545)

Vulnerability from cvelistv5 – Published: 2026-08-28 17:09 – Updated: 2026-08-28 17:09

Title

Yamcs: WebSocket subscription handlers omit the privilege checks their REST siblings enforce

Summary

Yamcs is a mission control framework. Prior to 5.12.8 and 5.13.2, Yamcs WebSocket subscription handlers fail to enforce the privileges required by equivalent REST endpoints. PacketsApi.subscribePackets exposes the packets WebSocket topic without ObjectPrivilegeType.ReadPacket, ProcessingApi.subscribeAlgorithmStatus exposes the algorithm-status WebSocket topic without ObjectPrivilegeType.ReadAlgorithm, and MdbOverrideApi.subscribeMdbChanges exposes the mdb-changes WebSocket topic without SystemPrivilege.GetMissionDatabase. A low-privilege authenticated user can receive telemetry packets, algorithm status, and mission database change information outside the assigned authorization scope. This issue is fixed in versions 5.12.8 and 5.13.2.

Severity

6.5 (Medium)


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

CWE

CWE-862 - Missing Authorization

Assigner

GitHub_M mitre root

References

5 references

URL	Tags
https://github.com/yamcs/yamcs/security/advisorie…	x_refsource_CONFIRM
https://github.com/yamcs/yamcs/commit/0691731846c…	x_refsource_MISC
https://github.com/yamcs/yamcs/commit/12864af555e…	x_refsource_MISC
https://github.com/yamcs/yamcs/releases/tag/yamcs…	x_refsource_MISC
https://github.com/yamcs/yamcs/releases/tag/yamcs…	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version	CPE status
yamcs	yamcs	Affected: < 5.12.8 Affected: >= 5.13.0, < 5.13.2	guessed

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "cna": {
      "affected": [
        {
          "product": "yamcs",
          "vendor": "yamcs",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 5.12.8"
            },
            {
              "status": "affected",
              "version": "\u003e= 5.13.0, \u003c 5.13.2"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Yamcs is a mission control framework. Prior to 5.12.8 and 5.13.2, Yamcs WebSocket subscription handlers fail to enforce the privileges required by equivalent REST endpoints. PacketsApi.subscribePackets exposes the packets WebSocket topic without ObjectPrivilegeType.ReadPacket, ProcessingApi.subscribeAlgorithmStatus exposes the algorithm-status WebSocket topic without ObjectPrivilegeType.ReadAlgorithm, and MdbOverrideApi.subscribeMdbChanges exposes the mdb-changes WebSocket topic without SystemPrivilege.GetMissionDatabase. A low-privilege authenticated user can receive telemetry packets, algorithm status, and mission database change information outside the assigned authorization scope. This issue is fixed in versions 5.12.8 and 5.13.2."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 6.5,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "NONE",
            "privilegesRequired": "LOW",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-862",
              "description": "CWE-862: Missing Authorization",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-28T17:09:53.114Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/yamcs/yamcs/security/advisories/GHSA-fwww-cp23-7f5g",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/yamcs/yamcs/security/advisories/GHSA-fwww-cp23-7f5g"
        },
        {
          "name": "https://github.com/yamcs/yamcs/commit/0691731846c5a0aca81b88fabbd2cd51d56fe076",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/yamcs/yamcs/commit/0691731846c5a0aca81b88fabbd2cd51d56fe076"
        },
        {
          "name": "https://github.com/yamcs/yamcs/commit/12864af555e6ca4941b01c1f1217859cc0492ce0",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/yamcs/yamcs/commit/12864af555e6ca4941b01c1f1217859cc0492ce0"
        },
        {
          "name": "https://github.com/yamcs/yamcs/releases/tag/yamcs-5.12.8",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/yamcs/yamcs/releases/tag/yamcs-5.12.8"
        },
        {
          "name": "https://github.com/yamcs/yamcs/releases/tag/yamcs-5.13.2",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/yamcs/yamcs/releases/tag/yamcs-5.13.2"
        }
      ],
      "source": {
        "advisory": "GHSA-fwww-cp23-7f5g",
        "discovery": "UNKNOWN"
      },
      "title": "Yamcs: WebSocket subscription handlers omit the privilege checks their REST siblings enforce"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-55545",
    "datePublished": "2026-08-28T17:09:53.114Z",
    "dateReserved": "2026-06-16T23:01:04.075Z",
    "dateUpdated": "2026-08-28T17:09:53.114Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-55545",
      "date": "2026-08-30",
      "epss": "0.00331",
      "percentile": "0.25623"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2026-55545\",\"sourceIdentifier\":\"security-advisories@github.com\",\"published\":\"2026-08-28T20:18:28.380\",\"lastModified\":\"2026-08-28T20:18:28.380\",\"vulnStatus\":\"Received\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"Yamcs is a mission control framework. Prior to 5.12.8 and 5.13.2, Yamcs WebSocket subscription handlers fail to enforce the privileges required by equivalent REST endpoints. PacketsApi.subscribePackets exposes the packets WebSocket topic without ObjectPrivilegeType.ReadPacket, ProcessingApi.subscribeAlgorithmStatus exposes the algorithm-status WebSocket topic without ObjectPrivilegeType.ReadAlgorithm, and MdbOverrideApi.subscribeMdbChanges exposes the mdb-changes WebSocket topic without SystemPrivilege.GetMissionDatabase. A low-privilege authenticated user can receive telemetry packets, algorithm status, and mission database change information outside the assigned authorization scope. This issue is fixed in versions 5.12.8 and 5.13.2.\"}],\"affected\":[{\"source\":\"security-advisories@github.com\",\"affectedData\":[{\"vendor\":\"yamcs\",\"product\":\"yamcs\",\"versions\":[{\"version\":\"\u003c 5.12.8\",\"status\":\"affected\"},{\"version\":\"\u003e= 5.13.0, \u003c 5.13.2\",\"status\":\"affected\"}]}]}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"security-advisories@github.com\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N\",\"baseScore\":6.5,\"baseSeverity\":\"MEDIUM\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"LOW\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"HIGH\",\"integrityImpact\":\"NONE\",\"availabilityImpact\":\"NONE\"},\"exploitabilityScore\":2.8,\"impactScore\":3.6}]},\"weaknesses\":[{\"source\":\"security-advisories@github.com\",\"type\":\"Primary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-862\"}]}],\"references\":[{\"url\":\"https://github.com/yamcs/yamcs/commit/0691731846c5a0aca81b88fabbd2cd51d56fe076\",\"source\":\"security-advisories@github.com\"},{\"url\":\"https://github.com/yamcs/yamcs/commit/12864af555e6ca4941b01c1f1217859cc0492ce0\",\"source\":\"security-advisories@github.com\"},{\"url\":\"https://github.com/yamcs/yamcs/releases/tag/yamcs-5.12.8\",\"source\":\"security-advisories@github.com\"},{\"url\":\"https://github.com/yamcs/yamcs/releases/tag/yamcs-5.13.2\",\"source\":\"security-advisories@github.com\"},{\"url\":\"https://github.com/yamcs/yamcs/security/advisories/GHSA-fwww-cp23-7f5g\",\"source\":\"security-advisories@github.com\"}]}}"
  }
}

FKIE_CVE-2026-55545

Vulnerability from fkie_nvd - Published: 2026-08-28 20:18 - Updated: 2026-08-28 20:18

Severity

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

Summary

References

	URL	Tags
	security-advisories@github.com	https://github.com/yamcs/yamcs/commit/0691731846c5a0aca81b88fabbd2cd51d56fe076
	security-advisories@github.com	https://github.com/yamcs/yamcs/commit/12864af555e6ca4941b01c1f1217859cc0492ce0
	security-advisories@github.com	https://github.com/yamcs/yamcs/releases/tag/yamcs-5.12.8
	security-advisories@github.com	https://github.com/yamcs/yamcs/releases/tag/yamcs-5.13.2
	security-advisories@github.com	https://github.com/yamcs/yamcs/security/advisories/GHSA-fwww-cp23-7f5g

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "yamcs",
          "vendor": "yamcs",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 5.12.8"
            },
            {
              "status": "affected",
              "version": "\u003e= 5.13.0, \u003c 5.13.2"
            }
          ]
        }
      ],
      "source": "security-advisories@github.com"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Yamcs is a mission control framework. Prior to 5.12.8 and 5.13.2, Yamcs WebSocket subscription handlers fail to enforce the privileges required by equivalent REST endpoints. PacketsApi.subscribePackets exposes the packets WebSocket topic without ObjectPrivilegeType.ReadPacket, ProcessingApi.subscribeAlgorithmStatus exposes the algorithm-status WebSocket topic without ObjectPrivilegeType.ReadAlgorithm, and MdbOverrideApi.subscribeMdbChanges exposes the mdb-changes WebSocket topic without SystemPrivilege.GetMissionDatabase. A low-privilege authenticated user can receive telemetry packets, algorithm status, and mission database change information outside the assigned authorization scope. This issue is fixed in versions 5.12.8 and 5.13.2."
    }
  ],
  "id": "CVE-2026-55545",
  "lastModified": "2026-08-28T20:18:28.380",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 6.5,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "NONE",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 2.8,
        "impactScore": 3.6,
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ]
  },
  "published": "2026-08-28T20:18:28.380",
  "references": [
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/yamcs/yamcs/commit/0691731846c5a0aca81b88fabbd2cd51d56fe076"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/yamcs/yamcs/commit/12864af555e6ca4941b01c1f1217859cc0492ce0"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/yamcs/yamcs/releases/tag/yamcs-5.12.8"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/yamcs/yamcs/releases/tag/yamcs-5.13.2"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/yamcs/yamcs/security/advisories/GHSA-fwww-cp23-7f5g"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Received",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-862"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Primary"
    }
  ]
}

GHSA-FWWW-CP23-7F5G

Vulnerability from github – Published: 2026-08-28 17:10 – Updated: 2026-08-28 17:10

Summary

Yamcs's WebSocket subscription handlers omit the privilege checks their REST siblings enforce

Details

Asset / scope: Yamcs 5.12.7 WebSocket topics (packets, algorithm-status, mdb-changes)

Summary

Several WebSocket subscription handlers do not perform the privilege check that their REST counterparts enforce, so a principal subscribing over WebSocket receives data the REST API would have scoped or denied.

Root cause

packets (PacketsApi.subscribePackets) performs no ReadPacket check, while the REST siblings do (listPackets:128, streamPackets:256, subscribeContainers:538). A principal with a narrow ReadPacket scope receives the raw binary of all TM packets on the processor.
algorithm-status (ProcessingApi.subscribeAlgorithmStatus) performs no check, while REST getAlgorithmStatus enforces checkObjectPrivileges(ReadAlgorithm, ...) (:467).
mdb-changes (MdbOverrideApi.subscribeMdbChanges) performs no check, while base MDB reads require GetMissionDatabase.

Remediation

Bring each WebSocket subscription handler to parity with its REST sibling's privilege check (ReadPacket, ReadAlgorithm, GetMissionDatabase). This is the same declarative fail-closed fix as Report 1.

Supporting material

Subsystem source audit of the WS-vs-REST authorization parity. Available on request.

Disclosure and credit

This was found by Cipher / Causal Security - https://causalsecurity.com/. We are coordinating disclosure via this report and request CVEs where you agree they qualify. We propose the 90-day window stated in your security policy. We might publish a write-up after a fix and the agreed window.

Severity

6.5 (Medium)


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

Show details on source website

JSON

To clipboard

{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 5.12.7"
      },
      "package": {
        "ecosystem": "Maven",
        "name": "org.yamcs:yamcs-core"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "5.12.8"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 5.13.1"
      },
      "package": {
        "ecosystem": "Maven",
        "name": "org.yamcs:yamcs-core"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "5.13.0"
            },
            {
              "fixed": "5.13.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-55545"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-862"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-08-28T17:10:26Z",
    "nvd_published_at": null,
    "severity": "MODERATE"
  },
  "details": "**Asset / scope:** Yamcs 5.12.7 WebSocket topics (`packets`, `algorithm-status`, `mdb-changes`)\n\n## Summary\n\nSeveral WebSocket subscription handlers do not perform the privilege check that their REST counterparts\nenforce, so a principal subscribing over WebSocket receives data the REST API would have scoped or denied.\n\n## Root cause\n\n- `packets` (`PacketsApi.subscribePackets`) performs no `ReadPacket` check, while the REST siblings do\n  (`listPackets:128`, `streamPackets:256`, `subscribeContainers:538`). A principal with a narrow\n  `ReadPacket` scope receives the raw binary of all TM packets on the processor.\n- `algorithm-status` (`ProcessingApi.subscribeAlgorithmStatus`) performs no check, while REST\n  `getAlgorithmStatus` enforces `checkObjectPrivileges(ReadAlgorithm, ...)` (`:467`).\n- `mdb-changes` (`MdbOverrideApi.subscribeMdbChanges`) performs no check, while base MDB reads require\n  `GetMissionDatabase`.\n\n## Remediation\n\nBring each WebSocket subscription handler to parity with its REST sibling\u0027s privilege check\n(`ReadPacket`, `ReadAlgorithm`, `GetMissionDatabase`). This is the same declarative fail-closed fix as\nReport 1.\n\n## Supporting material\n\nSubsystem source audit of the WS-vs-REST authorization parity. Available on request.\n\n--\n\n## Disclosure and credit\n\nThis was found by Cipher / Causal Security - https://causalsecurity.com/. We are coordinating disclosure\nvia this report and request CVEs where you agree they qualify. We propose the 90-day window stated in your\nsecurity policy. We might publish a write-up after a fix and the agreed window.",
  "id": "GHSA-fwww-cp23-7f5g",
  "modified": "2026-08-28T17:10:26Z",
  "published": "2026-08-28T17:10:26Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/yamcs/yamcs/security/advisories/GHSA-fwww-cp23-7f5g"
    },
    {
      "type": "WEB",
      "url": "https://github.com/yamcs/yamcs/commit/0691731846c5a0aca81b88fabbd2cd51d56fe076"
    },
    {
      "type": "WEB",
      "url": "https://github.com/yamcs/yamcs/commit/12864af555e6ca4941b01c1f1217859cc0492ce0"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/yamcs/yamcs"
    },
    {
      "type": "WEB",
      "url": "https://github.com/yamcs/yamcs/releases/tag/yamcs-5.12.8"
    },
    {
      "type": "WEB",
      "url": "https://github.com/yamcs/yamcs/releases/tag/yamcs-5.13.2"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Yamcs\u0027s WebSocket subscription handlers omit the privilege checks their REST siblings enforce"
}

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-2026-55545 (GCVE-0-2026-55545)

FKIE_CVE-2026-55545

GHSA-FWWW-CP23-7F5G

Summary

Root cause

Remediation

Supporting material

Disclosure and credit

Tags

Sightings

Nomenclature