CVE-2026-55521 (GCVE-0-2026-55521)

Vulnerability from cvelistv5 – Published: 2026-08-28 17:08 – Updated: 2026-08-28 19:52
VLAI
Title
Yamcs : Multiple Missing Function Level Access Control vulnerabilities in Yamcs Core API
Summary
Yamcs is a mission control framework. Prior to 5.12.8 and 5.13.2, Yamcs omits authorization checks in IndexesApi.listPacketIndex, IndexesApi.listEventIndex, Cop1Api.disable, Cop1Api.resume, Cop1Api.initialize, Cop1Api.updateConfig, and TimeApi.setTime. An authenticated low-privilege user can read packet and event index metadata without ObjectPrivilegeType.ReadPacket, alter COP-1 link state without SystemPrivilege.ControlLinks, and manipulate simulation time. These operations can disclose telemetry metadata, disrupt telecommand handling, and affect system integrity and availability. This issue is fixed in versions 5.12.8 and 5.13.2.
Severity
8.8 (High)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: poc Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-28 19:52 UTC
CWE
Assigner
References
Impacted products
Vendor Product Version CPE status
yamcs yamcs Affected: < 5.12.8
Affected: >= 5.13.0, < 5.13.2
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-55521",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-08-28T19:52:23.818416Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-08-28T19:52:43.290Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "references": [
          {
            "tags": [
              "exploit"
            ],
            "url": "https://github.com/yamcs/yamcs/security/advisories/GHSA-962x-ccwf-8x6p"
          }
        ],
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "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 omits authorization checks in IndexesApi.listPacketIndex, IndexesApi.listEventIndex, Cop1Api.disable, Cop1Api.resume, Cop1Api.initialize, Cop1Api.updateConfig, and TimeApi.setTime. An authenticated low-privilege user can read packet and event index metadata without ObjectPrivilegeType.ReadPacket, alter COP-1 link state without SystemPrivilege.ControlLinks, and manipulate simulation time. These operations can disclose telemetry metadata, disrupt telecommand handling, and affect system integrity and availability. This issue is fixed in versions 5.12.8 and 5.13.2."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 8.8,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "LOW",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-862",
              "description": "CWE-862: Missing Authorization",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-28T17:08:16.725Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/yamcs/yamcs/security/advisories/GHSA-962x-ccwf-8x6p",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/yamcs/yamcs/security/advisories/GHSA-962x-ccwf-8x6p"
        },
        {
          "name": "https://github.com/yamcs/yamcs/commit/405139afa6094dfaf63ac17f32df1f808846c950",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/yamcs/yamcs/commit/405139afa6094dfaf63ac17f32df1f808846c950"
        },
        {
          "name": "https://github.com/yamcs/yamcs/commit/493563679f838b86f3cdc5da9451d4a050ff6bd9",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/yamcs/yamcs/commit/493563679f838b86f3cdc5da9451d4a050ff6bd9"
        },
        {
          "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-962x-ccwf-8x6p",
        "discovery": "UNKNOWN"
      },
      "title": "Yamcs : Multiple Missing Function Level Access Control vulnerabilities in Yamcs Core API"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-55521",
    "datePublished": "2026-08-28T17:08:16.725Z",
    "dateReserved": "2026-06-16T22:44:22.284Z",
    "dateUpdated": "2026-08-28T19:52:43.290Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-55521",
      "date": "2026-08-30",
      "epss": "0.00361",
      "percentile": "0.28981"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2026-55521\",\"sourceIdentifier\":\"security-advisories@github.com\",\"published\":\"2026-08-28T20:18:28.240\",\"lastModified\":\"2026-08-28T22:16:50.857\",\"vulnStatus\":\"Received\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"Yamcs is a mission control framework. Prior to 5.12.8 and 5.13.2, Yamcs omits authorization checks in IndexesApi.listPacketIndex, IndexesApi.listEventIndex, Cop1Api.disable, Cop1Api.resume, Cop1Api.initialize, Cop1Api.updateConfig, and TimeApi.setTime. An authenticated low-privilege user can read packet and event index metadata without ObjectPrivilegeType.ReadPacket, alter COP-1 link state without SystemPrivilege.ControlLinks, and manipulate simulation time. These operations can disclose telemetry metadata, disrupt telecommand handling, and affect system integrity and availability. 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:H/A:H\",\"baseScore\":8.8,\"baseSeverity\":\"HIGH\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"LOW\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"HIGH\",\"integrityImpact\":\"HIGH\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":2.8,\"impactScore\":5.9}],\"ssvcV203\":[{\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\",\"ssvcData\":{\"timestamp\":\"2026-08-28T19:52:23.818416Z\",\"id\":\"CVE-2026-55521\",\"options\":[{\"exploitation\":\"poc\"},{\"automatable\":\"no\"},{\"technicalImpact\":\"total\"}],\"role\":\"CISA Coordinator\",\"version\":\"2.0.3\"}}]},\"weaknesses\":[{\"source\":\"security-advisories@github.com\",\"type\":\"Secondary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-862\"}]}],\"references\":[{\"url\":\"https://github.com/yamcs/yamcs/commit/405139afa6094dfaf63ac17f32df1f808846c950\",\"source\":\"security-advisories@github.com\"},{\"url\":\"https://github.com/yamcs/yamcs/commit/493563679f838b86f3cdc5da9451d4a050ff6bd9\",\"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-962x-ccwf-8x6p\",\"source\":\"security-advisories@github.com\"},{\"url\":\"https://github.com/yamcs/yamcs/security/advisories/GHSA-962x-ccwf-8x6p\",\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\"}]}}",
    "vulnrichment": {
      "containers": "{\"adp\": [{\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2026-55521\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"poc\"}, {\"Automatable\": \"no\"}, {\"Technical Impact\": \"total\"}], \"version\": \"2.0.3\", \"timestamp\": \"2026-08-28T19:52:23.818416Z\"}}}], \"references\": [{\"url\": \"https://github.com/yamcs/yamcs/security/advisories/GHSA-962x-ccwf-8x6p\", \"tags\": [\"exploit\"]}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2026-08-28T19:52:35.361Z\"}}], \"cna\": {\"title\": \"Yamcs : Multiple Missing Function Level Access Control vulnerabilities in Yamcs Core API\", \"source\": {\"advisory\": \"GHSA-962x-ccwf-8x6p\", \"discovery\": \"UNKNOWN\"}, \"metrics\": [{\"cvssV3_1\": {\"scope\": \"UNCHANGED\", \"version\": \"3.1\", \"baseScore\": 8.8, \"attackVector\": \"NETWORK\", \"baseSeverity\": \"HIGH\", \"vectorString\": \"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H\", \"integrityImpact\": \"HIGH\", \"userInteraction\": \"NONE\", \"attackComplexity\": \"LOW\", \"availabilityImpact\": \"HIGH\", \"privilegesRequired\": \"LOW\", \"confidentialityImpact\": \"HIGH\"}}], \"affected\": [{\"vendor\": \"yamcs\", \"product\": \"yamcs\", \"versions\": [{\"status\": \"affected\", \"version\": \"\u003c 5.12.8\"}, {\"status\": \"affected\", \"version\": \"\u003e= 5.13.0, \u003c 5.13.2\"}]}], \"references\": [{\"url\": \"https://github.com/yamcs/yamcs/security/advisories/GHSA-962x-ccwf-8x6p\", \"name\": \"https://github.com/yamcs/yamcs/security/advisories/GHSA-962x-ccwf-8x6p\", \"tags\": [\"x_refsource_CONFIRM\"]}, {\"url\": \"https://github.com/yamcs/yamcs/commit/405139afa6094dfaf63ac17f32df1f808846c950\", \"name\": \"https://github.com/yamcs/yamcs/commit/405139afa6094dfaf63ac17f32df1f808846c950\", \"tags\": [\"x_refsource_MISC\"]}, {\"url\": \"https://github.com/yamcs/yamcs/commit/493563679f838b86f3cdc5da9451d4a050ff6bd9\", \"name\": \"https://github.com/yamcs/yamcs/commit/493563679f838b86f3cdc5da9451d4a050ff6bd9\", \"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-5.12.8\", \"tags\": [\"x_refsource_MISC\"]}, {\"url\": \"https://github.com/yamcs/yamcs/releases/tag/yamcs-5.13.2\", \"name\": \"https://github.com/yamcs/yamcs/releases/tag/yamcs-5.13.2\", \"tags\": [\"x_refsource_MISC\"]}], \"descriptions\": [{\"lang\": \"en\", \"value\": \"Yamcs is a mission control framework. Prior to 5.12.8 and 5.13.2, Yamcs omits authorization checks in IndexesApi.listPacketIndex, IndexesApi.listEventIndex, Cop1Api.disable, Cop1Api.resume, Cop1Api.initialize, Cop1Api.updateConfig, and TimeApi.setTime. An authenticated low-privilege user can read packet and event index metadata without ObjectPrivilegeType.ReadPacket, alter COP-1 link state without SystemPrivilege.ControlLinks, and manipulate simulation time. These operations can disclose telemetry metadata, disrupt telecommand handling, and affect system integrity and availability. This issue is fixed in versions 5.12.8 and 5.13.2.\"}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-862\", \"description\": \"CWE-862: Missing Authorization\"}]}], \"providerMetadata\": {\"orgId\": \"a0819718-46f1-4df5-94e2-005712e83aaa\", \"shortName\": \"GitHub_M\", \"dateUpdated\": \"2026-08-28T17:08:16.725Z\"}}}",
      "cveMetadata": "{\"cveId\": \"CVE-2026-55521\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-08-28T19:52:43.290Z\", \"dateReserved\": \"2026-06-16T22:44:22.284Z\", \"assignerOrgId\": \"a0819718-46f1-4df5-94e2-005712e83aaa\", \"datePublished\": \"2026-08-28T17:08:16.725Z\", \"assignerShortName\": \"GitHub_M\"}",
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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.