Vulnerability-Lookup

WID-SEC-W-2026-2400

Vulnerability from csaf_certbund - Published: 2026-07-16 22:00 - Updated: 2026-07-16 22:00

Summary

Microsoft Office 365 (Moodle Plugin): Schwachstelle ermöglicht Umgehen von Sicherheitsvorkehrungen

Severity

Hoch

Notes

Das BSI ist als Anbieter für die eigenen, zur Nutzung bereitgestellten Inhalte nach den allgemeinen Gesetzen verantwortlich. Nutzerinnen und Nutzer sind jedoch dafür verantwortlich, die Verwendung und/oder die Umsetzung der mit den Inhalten bereitgestellten Informationen sorgfältig im Einzelfall zu prüfen.

Produktbeschreibung: Die Microsoft Office Suite beinhaltet zahlreiche Büroanwendungen wie Textverarbeitung, Tabellenkalkulation, Datenbank und weitere Applikationen.

Angriff: Ein entfernter, anonymer Angreifer kann eine Schwachstelle in Microsoft Office 365 (Moodle Plugin) ausnutzen, um Sicherheitsvorkehrungen zu umgehen, Benutzer zu imitieren und sich so erweiterte Berechtigungen, einschließlich Administratorzugriff, zu verschaffen.

Betroffene Betriebssysteme: - Android - iPhoneOS - Linux - UNIX - Windows

CVE-2026-54733

Affected products

Known affected 3 products

Product	Identifier	Version	Remediation
Microsoft Office 365 Moodle Plugin <4.5.6 Microsoft / Office 365		Moodle Plugin <4.5.6
Microsoft Office 365 Moodle Plugin <5.0.5 Microsoft / Office 365		Moodle Plugin <5.0.5
Microsoft Office 365 Moodle Plugin <5.1.1 Microsoft / Office 365		Moodle Plugin <5.1.1

References

3 references

URL	Category
https://wid.cert-bund.de/.well-known/csaf/white/2…	self
https://wid.cert-bund.de/portal/wid/securityadvis…	self
https://github.com/microsoft/o365-moodle/security…	external

JSON

To clipboard

{
  "document": {
    "aggregate_severity": {
      "text": "hoch"
    },
    "category": "csaf_base",
    "csaf_version": "2.0",
    "distribution": {
      "tlp": {
        "label": "WHITE",
        "url": "https://www.first.org/tlp/"
      }
    },
    "lang": "de-DE",
    "notes": [
      {
        "category": "legal_disclaimer",
        "text": "Das BSI ist als Anbieter f\u00fcr die eigenen, zur Nutzung bereitgestellten Inhalte nach den allgemeinen Gesetzen verantwortlich. Nutzerinnen und Nutzer sind jedoch daf\u00fcr verantwortlich, die Verwendung und/oder die Umsetzung der mit den Inhalten bereitgestellten Informationen sorgf\u00e4ltig im Einzelfall zu pr\u00fcfen."
      },
      {
        "category": "description",
        "text": "Die Microsoft Office Suite beinhaltet zahlreiche B\u00fcroanwendungen wie Textverarbeitung, Tabellenkalkulation, Datenbank und weitere Applikationen.",
        "title": "Produktbeschreibung"
      },
      {
        "category": "summary",
        "text": "Ein entfernter, anonymer Angreifer kann eine Schwachstelle in Microsoft Office 365 (Moodle Plugin) ausnutzen, um Sicherheitsvorkehrungen zu umgehen, Benutzer zu imitieren und sich so erweiterte Berechtigungen, einschlie\u00dflich Administratorzugriff, zu verschaffen.",
        "title": "Angriff"
      },
      {
        "category": "general",
        "text": "- Android\n- iPhoneOS\n- Linux\n- UNIX\n- Windows",
        "title": "Betroffene Betriebssysteme"
      }
    ],
    "publisher": {
      "category": "other",
      "contact_details": "csaf-provider@cert-bund.de",
      "name": "Bundesamt f\u00fcr Sicherheit in der Informationstechnik",
      "namespace": "https://www.bsi.bund.de"
    },
    "references": [
      {
        "category": "self",
        "summary": "WID-SEC-W-2026-2400 - CSAF Version",
        "url": "https://wid.cert-bund.de/.well-known/csaf/white/2026/wid-sec-w-2026-2400.json"
      },
      {
        "category": "self",
        "summary": "WID-SEC-2026-2400 - Portal Version",
        "url": "https://wid.cert-bund.de/portal/wid/securityadvisory?name=WID-SEC-2026-2400"
      },
      {
        "category": "external",
        "summary": "GitHub Security Advisory GHSA-hqjh-93qv-47v5 vom 2026-07-16",
        "url": "https://github.com/microsoft/o365-moodle/security/advisories/GHSA-hqjh-93qv-47v5"
      }
    ],
    "source_lang": "en-US",
    "title": "Microsoft Office 365 (Moodle Plugin): Schwachstelle erm\u00f6glicht Umgehen von Sicherheitsvorkehrungen",
    "tracking": {
      "current_release_date": "2026-07-16T22:00:00.000+00:00",
      "generator": {
        "date": "2026-07-17T10:50:04.600+00:00",
        "engine": {
          "name": "BSI-WID",
          "version": "1.6.0"
        }
      },
      "id": "WID-SEC-W-2026-2400",
      "initial_release_date": "2026-07-16T22:00:00.000+00:00",
      "revision_history": [
        {
          "date": "2026-07-16T22:00:00.000+00:00",
          "number": "1",
          "summary": "Initiale Fassung"
        }
      ],
      "status": "final",
      "version": "1"
    }
  },
  "product_tree": {
    "branches": [
      {
        "branches": [
          {
            "branches": [
              {
                "category": "product_version_range",
                "name": "Moodle Plugin \u003c4.5.6",
                "product": {
                  "name": "Microsoft Office 365 Moodle Plugin \u003c4.5.6",
                  "product_id": "T056750"
                }
              },
              {
                "category": "product_version",
                "name": "Moodle Plugin 4.5.6",
                "product": {
                  "name": "Microsoft Office 365 Moodle Plugin 4.5.6",
                  "product_id": "T056750-fixed",
                  "product_identification_helper": {
                    "cpe": "cpe:/a:microsoft:office_365:moodle_plugin__4.5.6"
                  }
                }
              },
              {
                "category": "product_version_range",
                "name": "Moodle Plugin \u003c5.0.5",
                "product": {
                  "name": "Microsoft Office 365 Moodle Plugin \u003c5.0.5",
                  "product_id": "T056751"
                }
              },
              {
                "category": "product_version",
                "name": "Moodle Plugin 5.0.5",
                "product": {
                  "name": "Microsoft Office 365 Moodle Plugin 5.0.5",
                  "product_id": "T056751-fixed",
                  "product_identification_helper": {
                    "cpe": "cpe:/a:microsoft:office_365:moodle_plugin__5.0.5"
                  }
                }
              },
              {
                "category": "product_version_range",
                "name": "Moodle Plugin \u003c5.1.1",
                "product": {
                  "name": "Microsoft Office 365 Moodle Plugin \u003c5.1.1",
                  "product_id": "T056752"
                }
              },
              {
                "category": "product_version",
                "name": "Moodle Plugin 5.1.1",
                "product": {
                  "name": "Microsoft Office 365 Moodle Plugin 5.1.1",
                  "product_id": "T056752-fixed",
                  "product_identification_helper": {
                    "cpe": "cpe:/a:microsoft:office_365:moodle_plugin__5.1.1"
                  }
                }
              }
            ],
            "category": "product_name",
            "name": "Office 365"
          }
        ],
        "category": "vendor",
        "name": "Microsoft"
      }
    ]
  },
  "vulnerabilities": [
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      "product_status": {
        "known_affected": [
          "T056750",
          "T056751",
          "T056752"
        ]
      },
      "release_date": "2026-07-16T22:00:00.000+00:00",
      "title": "CVE-2026-54733"
    }
  ]
}

CVE-2026-54733 (GCVE-0-2026-54733)

Vulnerability from cvelistv5 – Published: 2026-07-16 14:52 – Updated: 2026-07-16 15:35

Title

moodle-local_o365: Authentication bypass via unverified JWT signature in Teams SSO endpoint

Summary

The Microsoft 365 and Microsoft Entra ID Plugins for Moodle provide Office 365 and Azure Active Directory integration for Moodle. Prior to 4.5.6, 5.0.5, and 5.1.1, the Microsoft Office 365 Integration plugin local_o365 Teams SSO endpoint sso_login.php base64-decodes a JWT payload and authenticates users from the upn claim without verifying the JWT signature, allowing an unauthenticated attacker to forge a token and obtain a Moodle session as an O365-authenticated user. This issue is fixed in versions 4.5.6, 5.0.5, and 5.1.1.

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

SSVC

Exploitation: none Automatable: yes Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-07-16 15:34 UTC

CWE

CWE-347 - Improper Verification of Cryptographic Signature

Assigner

GitHub_M mitre root Scorecard

References

7 references

URL	Tags
https://github.com/microsoft/o365-moodle/security…	x_refsource_CONFIRM
https://github.com/microsoft/o365-moodle/commit/0…	x_refsource_MISC
https://github.com/microsoft/o365-moodle/commit/2…	x_refsource_MISC
https://github.com/microsoft/o365-moodle/commit/d…	x_refsource_MISC
https://github.com/microsoft/o365-moodle/releases…	x_refsource_MISC
https://github.com/microsoft/o365-moodle/releases…	x_refsource_MISC
https://github.com/microsoft/o365-moodle/releases…	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version
microsoft	o365-moodle	Affected: < 4.5.6 Affected: >= 5.0.0, < 5.0.5 Affected: >= 5.1.0, < 5.1.1

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-54733",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-07-16T15:34:47.399720Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-07-16T15:35:02.951Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "o365-moodle",
          "vendor": "microsoft",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 4.5.6"
            },
            {
              "status": "affected",
              "version": "\u003e= 5.0.0, \u003c 5.0.5"
            },
            {
              "status": "affected",
              "version": "\u003e= 5.1.0, \u003c 5.1.1"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "The Microsoft 365 and Microsoft Entra ID Plugins for Moodle provide Office 365 and Azure Active Directory integration for Moodle. Prior to 4.5.6, 5.0.5, and 5.1.1, the Microsoft Office 365 Integration plugin local_o365 Teams SSO endpoint sso_login.php base64-decodes a JWT payload and authenticates users from the upn claim without verifying the JWT signature, allowing an unauthenticated attacker to forge a token and obtain a Moodle session as an O365-authenticated user. This issue is fixed in versions 4.5.6, 5.0.5, and 5.1.1."
        }
      ],
      "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"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-347",
              "description": "CWE-347: Improper Verification of Cryptographic Signature",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-07-16T14:52:03.389Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
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      },
      "references": [
        {
          "name": "https://github.com/microsoft/o365-moodle/security/advisories/GHSA-hqjh-93qv-47v5",
          "tags": [
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          ],
          "url": "https://github.com/microsoft/o365-moodle/security/advisories/GHSA-hqjh-93qv-47v5"
        },
        {
          "name": "https://github.com/microsoft/o365-moodle/commit/01b2d4c2e13b06a66557527084cbf9bace655944",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/microsoft/o365-moodle/commit/01b2d4c2e13b06a66557527084cbf9bace655944"
        },
        {
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          "url": "https://github.com/microsoft/o365-moodle/commit/258872f6e2011f4efa8ebb77d2898142a9435e89"
        },
        {
          "name": "https://github.com/microsoft/o365-moodle/commit/d5596655f0baaee0f11aec2e10d6f36b0bd29220",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/microsoft/o365-moodle/commit/d5596655f0baaee0f11aec2e10d6f36b0bd29220"
        },
        {
          "name": "https://github.com/microsoft/o365-moodle/releases/tag/v20260423_m405",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/microsoft/o365-moodle/releases/tag/v20260423_m405"
        },
        {
          "name": "https://github.com/microsoft/o365-moodle/releases/tag/v20260423_m500",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/microsoft/o365-moodle/releases/tag/v20260423_m500"
        },
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    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-54733",
    "datePublished": "2026-07-16T14:52:03.389Z",
    "dateReserved": "2026-06-15T23:07:33.232Z",
    "dateUpdated": "2026-07-16T15:35:02.951Z",
    "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.

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.

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WID-SEC-W-2026-2400

CVE-2026-54733 (GCVE-0-2026-54733)

Tags

Sightings

Nomenclature

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