Vulnerability-Lookup

GHSA-8MXQ-7XR7-2FXJ

Vulnerability from github – Published: 2026-04-03 21:42 – Updated: 2026-04-06 23:10

Summary

LTI JupyterHub Authenticator: Unbounded Memory Growth via Nonce Storage (Denial of Service)

Details

Summary

The LTI 1.1 validator stores OAuth nonces in a class-level dictionary that grows without bounds. Nonces are added before signature validation, so an attacker with knowledge of a valid consumer key can send repeated requests with unique nonces to gradually exhaust server memory, causing a denial of service.

Patches

upgrade jupyterhub-litauthenticator to 1.6.3

Severity

5.9 (Medium)


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

Show details on source website

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{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 1.6.2"
      },
      "package": {
        "ecosystem": "PyPI",
        "name": "jupyterhub-ltiauthenticator"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.6.3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-34052"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-401",
      "CWE-770"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-04-03T21:42:35Z",
    "nvd_published_at": "2026-04-03T23:17:03Z",
    "severity": "MODERATE"
  },
  "details": "## Summary\n\nThe LTI 1.1 validator stores OAuth nonces in a class-level dictionary that grows without bounds. Nonces are added before signature validation, so an attacker with knowledge of a valid consumer key can send repeated requests with unique nonces to gradually exhaust server memory, causing a denial of service.\n\n## Patches\n\n- upgrade jupyterhub-litauthenticator to 1.6.3",
  "id": "GHSA-8mxq-7xr7-2fxj",
  "modified": "2026-04-06T23:10:01Z",
  "published": "2026-04-03T21:42:35Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/jupyterhub/ltiauthenticator/security/advisories/GHSA-8mxq-7xr7-2fxj"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-34052"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/jupyterhub/ltiauthenticator"
    },
    {
      "type": "WEB",
      "url": "https://github.com/jupyterhub/ltiauthenticator/releases/tag/1.6.3"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "LTI JupyterHub Authenticator: Unbounded Memory Growth via Nonce Storage (Denial of Service)"
}

CVE-2026-34052 (GCVE-0-2026-34052)

Vulnerability from cvelistv5 – Published: 2026-04-03 22:04 – Updated: 2026-04-06 18:59

Title

LTI JupyterHub Authenticator: Unbounded Memory Growth via Nonce Storage (Denial of Service)

Summary

LTI JupyterHub Authenticator is a JupyterHub authenticator for LTI. Prior to version 1.6.3, the LTI 1.1 validator stores OAuth nonces in a class-level dictionary that grows without bounds. Nonces are added before signature validation, so an attacker with knowledge of a valid consumer key can send repeated requests with unique nonces to gradually exhaust server memory, causing a denial of service. This issue has been patched in version 1.6.3.

Severity

5.9 (Medium)


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

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-04-06 18:58 UTC

CWE

CWE-401 - Missing Release of Memory after Effective Lifetime
CWE-770 - Allocation of Resources Without Limits or Throttling

Assigner

GitHub_M mitre root

References

2 references

URL	Tags
https://github.com/jupyterhub/ltiauthenticator/se…	x_refsource_CONFIRM
https://github.com/jupyterhub/ltiauthenticator/re…	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version
jupyterhub	ltiauthenticator	Affected: < 1.6.3

Show details on NVD website

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{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-34052",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-04-06T18:58:43.478477Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-04-06T18:59:04.966Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "ltiauthenticator",
          "vendor": "jupyterhub",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 1.6.3"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "LTI JupyterHub Authenticator is a JupyterHub authenticator for LTI. Prior to version 1.6.3, the LTI 1.1 validator stores OAuth nonces in a class-level dictionary that grows without bounds. Nonces are added before signature validation, so an attacker with knowledge of a valid consumer key can send repeated requests with unique nonces to gradually exhaust server memory, causing a denial of service. This issue has been patched in version 1.6.3."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "HIGH",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 5.9,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "NONE",
            "integrityImpact": "NONE",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-401",
              "description": "CWE-401: Missing Release of Memory after Effective Lifetime",
              "lang": "en",
              "type": "CWE"
            }
          ]
        },
        {
          "descriptions": [
            {
              "cweId": "CWE-770",
              "description": "CWE-770: Allocation of Resources Without Limits or Throttling",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-04-03T22:04:10.519Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/jupyterhub/ltiauthenticator/security/advisories/GHSA-8mxq-7xr7-2fxj",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/jupyterhub/ltiauthenticator/security/advisories/GHSA-8mxq-7xr7-2fxj"
        },
        {
          "name": "https://github.com/jupyterhub/ltiauthenticator/releases/tag/1.6.3",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/jupyterhub/ltiauthenticator/releases/tag/1.6.3"
        }
      ],
      "source": {
        "advisory": "GHSA-8mxq-7xr7-2fxj",
        "discovery": "UNKNOWN"
      },
      "title": "LTI JupyterHub Authenticator: Unbounded Memory Growth via Nonce Storage (Denial of Service)"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-34052",
    "datePublished": "2026-04-03T22:04:10.519Z",
    "dateReserved": "2026-03-25T15:29:04.746Z",
    "dateUpdated": "2026-04-06T18:59:04.966Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

PYSEC-2026-2533

Vulnerability from pysec - Published: 2026-07-13 14:36 - Updated: 2026-07-13 16:04

Details

Summary

Patches

upgrade jupyterhub-litauthenticator to 1.6.3

Severity

5.9 (Medium)


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

Impacted products

Name	purl
jupyterhub-ltiauthenticator	pkg:pypi/jupyterhub-ltiauthenticator

Aliases

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "jupyterhub-ltiauthenticator",
        "purl": "pkg:pypi/jupyterhub-ltiauthenticator"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.6.3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.1",
        "0.2",
        "0.3",
        "0.4.0",
        "1.0.0",
        "1.1.0",
        "1.2.0",
        "1.3.0",
        "1.4.0",
        "1.5.0",
        "1.5.1",
        "1.6.0",
        "1.6.1",
        "1.6.2"
      ]
    }
  ],
  "aliases": [
    "CVE-2026-34052",
    "GHSA-8mxq-7xr7-2fxj"
  ],
  "details": "## Summary\n\nThe LTI 1.1 validator stores OAuth nonces in a class-level dictionary that grows without bounds. Nonces are added before signature validation, so an attacker with knowledge of a valid consumer key can send repeated requests with unique nonces to gradually exhaust server memory, causing a denial of service.\n\n## Patches\n\n- upgrade jupyterhub-litauthenticator to 1.6.3",
  "id": "PYSEC-2026-2533",
  "modified": "2026-07-13T16:04:22.882070Z",
  "published": "2026-07-13T14:36:47.380994Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/jupyterhub/ltiauthenticator/security/advisories/GHSA-8mxq-7xr7-2fxj"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-34052"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/jupyterhub/ltiauthenticator"
    },
    {
      "type": "WEB",
      "url": "https://github.com/jupyterhub/ltiauthenticator/releases/tag/1.6.3"
    },
    {
      "type": "PACKAGE",
      "url": "https://pypi.org/project/jupyterhub-ltiauthenticator"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/advisories/GHSA-8mxq-7xr7-2fxj"
    }
  ],
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "LTI JupyterHub Authenticator: Unbounded Memory Growth via Nonce Storage (Denial of Service)"
}

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.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.

Action not permitted

GHSA-8MXQ-7XR7-2FXJ

Summary

Patches

CVE-2026-34052 (GCVE-0-2026-34052)

PYSEC-2026-2533

Summary

Patches

Tags

Sightings

Nomenclature

Related by attack behaviour