Vulnerability-Lookup

CVE-2026-53636 (GCVE-0-2026-53636)

Vulnerability from cvelistv5 – Published: 2026-09-02 16:54 – Updated: 2026-09-02 18:03

Title

Open edX LTI OAuth Replay Attack

Summary

Open edX Platform enables the authoring and delivery of online learning at any scale. Prior to commit 3a5ac85, a security vulnerability has been identified in the Open edX LMS platform's LTI (Learning Tools Interoperability) Provider implementation. The validate_timestamp_and_nonce function in lms/djangoapps/lti_provider/signature_validator.py does not validate OAuth nonces or timestamps, allowing an attacker who captures a valid LTI launch request to replay it an unlimited number of times without detection. This issue has been patched via commit 3a5ac85.

Severity

4.7 (Medium)


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

SSVC

Exploitation: poc Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-09-02 18:03 UTC

CWE

CWE-294 - Authentication Bypass by Capture-replay

Assigner

GitHub_M mitre root

References

4 references

URL	Tags
https://github.com/openedx/openedx-platform/secur…	x_refsource_CONFIRM
https://github.com/openedx/openedx-platform/commi…	x_refsource_MISC
https://github.com/openedx/openedx-platform/commi…	x_refsource_MISC
https://github.com/openedx/openedx-platform/commi…	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version	CPE status
openedx	openedx-platform	Affected: < 3a5ac856c79557c5c74d8b3e6578f289d7cceecd	guessed

Show details on NVD website

JSON

To clipboard

{
  "containers": {
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        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-53636",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-09-02T18:03:21.512059Z",
                "version": "2.0.3"
              },
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        ],
        "providerMetadata": {
          "dateUpdated": "2026-09-02T18:03:41.926Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "references": [
          {
            "tags": [
              "exploit"
            ],
            "url": "https://github.com/openedx/openedx-platform/security/advisories/GHSA-6gm5-c49g-p3h9"
          }
        ],
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
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          "product": "openedx-platform",
          "vendor": "openedx",
          "versions": [
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          "value": "Open edX Platform enables the authoring and delivery of online learning at any scale. Prior to commit 3a5ac85, a security vulnerability has been identified in the Open edX LMS platform\u0027s LTI (Learning Tools Interoperability) Provider implementation. The validate_timestamp_and_nonce function in lms/djangoapps/lti_provider/signature_validator.py does not validate OAuth nonces or timestamps, allowing an attacker who captures a valid LTI launch request to replay it an unlimited number of times without detection. This issue has been patched via commit 3a5ac85."
        }
      ],
      "metrics": [
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          "cvssV3_1": {
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            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 4.7,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "LOW",
            "integrityImpact": "LOW",
            "privilegesRequired": "NONE",
            "scope": "CHANGED",
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      "providerMetadata": {
        "dateUpdated": "2026-09-02T16:54:10.403Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/openedx/openedx-platform/security/advisories/GHSA-6gm5-c49g-p3h9",
          "tags": [
            "x_refsource_CONFIRM"
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          "url": "https://github.com/openedx/openedx-platform/security/advisories/GHSA-6gm5-c49g-p3h9"
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          "tags": [
            "x_refsource_MISC"
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          "url": "https://github.com/openedx/openedx-platform/commit/0a92cf25de8844bf840ffd5d18dcfd940031a2ba"
        },
        {
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          "tags": [
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        },
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          "url": "https://github.com/openedx/openedx-platform/commit/50af17b05d82a8c7e8e690cc2783a8a0ba330bc3"
        }
      ],
      "source": {
        "advisory": "GHSA-6gm5-c49g-p3h9",
        "discovery": "UNKNOWN"
      },
      "title": "Open edX LTI OAuth Replay Attack"
    }
  },
  "cveMetadata": {
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    "assignerShortName": "GitHub_M",
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    "datePublished": "2026-09-02T16:54:10.403Z",
    "dateReserved": "2026-06-09T20:16:59.647Z",
    "dateUpdated": "2026-09-02T18:03:41.926Z",
    "state": "PUBLISHED"
  },
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  }
}

FKIE_CVE-2026-53636

Vulnerability from fkie_nvd - Published: 2026-09-02 17:17 - Updated: 2026-09-02 19:17

Severity

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

Summary

References

	URL	Tags
	security-advisories@github.com	https://github.com/openedx/openedx-platform/commit/0a92cf25de8844bf840ffd5d18dcfd940031a2ba
	security-advisories@github.com	https://github.com/openedx/openedx-platform/commit/3a5ac856c79557c5c74d8b3e6578f289d7cceecd
	security-advisories@github.com	https://github.com/openedx/openedx-platform/commit/50af17b05d82a8c7e8e690cc2783a8a0ba330bc3
	security-advisories@github.com	https://github.com/openedx/openedx-platform/security/advisories/GHSA-6gm5-c49g-p3h9
	134c704f-9b21-4f2e-91b3-4a467353bcc0	https://github.com/openedx/openedx-platform/security/advisories/GHSA-6gm5-c49g-p3h9

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "openedx-platform",
          "vendor": "openedx",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 3a5ac856c79557c5c74d8b3e6578f289d7cceecd"
            }
          ]
        }
      ],
      "source": "security-advisories@github.com"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Open edX Platform enables the authoring and delivery of online learning at any scale. Prior to commit 3a5ac85, a security vulnerability has been identified in the Open edX LMS platform\u0027s LTI (Learning Tools Interoperability) Provider implementation. The validate_timestamp_and_nonce function in lms/djangoapps/lti_provider/signature_validator.py does not validate OAuth nonces or timestamps, allowing an attacker who captures a valid LTI launch request to replay it an unlimited number of times without detection. This issue has been patched via commit 3a5ac85."
    }
  ],
  "id": "CVE-2026-53636",
  "lastModified": "2026-09-02T19:17:21.457",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "HIGH",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 4.7,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "LOW",
          "integrityImpact": "LOW",
          "privilegesRequired": "NONE",
          "scope": "CHANGED",
          "userInteraction": "REQUIRED",
          "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:L/A:N",
          "version": "3.1"
        },
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        "impactScore": 2.7,
        "source": "security-advisories@github.com",
        "type": "Secondary"
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    "ssvcV203": [
      {
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          "version": "2.0.3"
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  "published": "2026-09-02T17:17:45.917",
  "references": [
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      "url": "https://github.com/openedx/openedx-platform/commit/0a92cf25de8844bf840ffd5d18dcfd940031a2ba"
    },
    {
      "source": "security-advisories@github.com",
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    {
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      "url": "https://github.com/openedx/openedx-platform/commit/50af17b05d82a8c7e8e690cc2783a8a0ba330bc3"
    },
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      "source": "security-advisories@github.com",
      "url": "https://github.com/openedx/openedx-platform/security/advisories/GHSA-6gm5-c49g-p3h9"
    },
    {
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
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    }
  ],
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  "vulnStatus": "Received",
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    {
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        {
          "lang": "en",
          "value": "CWE-294"
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      ],
      "source": "security-advisories@github.com",
      "type": "Secondary"
    }
  ]
}

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-2026-53636 (GCVE-0-2026-53636)

FKIE_CVE-2026-53636

Tags

Sightings

Nomenclature