Vulnerability-Lookup

GHSA-2299-GHJR-6VJP

Vulnerability from github – Published: 2026-03-24 19:48 – Updated: 2026-03-27 21:54

Summary

Parse Server: MFA recovery code single-use bypass via concurrent requests

Details

Impact

An attacker who obtains a user's password and a single MFA recovery code can reuse that recovery code an unlimited number of times by sending concurrent login requests. This defeats the single-use design of recovery codes. The attack requires the user's password, a valid recovery code, and the ability to send concurrent requests within milliseconds.

Patches

The login handler now uses optimistic locking when updating auth data that contains consumed single-use tokens. If a concurrent request has already modified the recovery array, the update fails and the login is rejected.

Workarounds

There are no known workarounds.

Severity

2.1 (Low)


                  
                    CVSS:4.0/AV:N/AC:H/AT:P/PR:H/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N

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JSON

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{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "parse-server"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "9.0.0"
            },
            {
              "fixed": "9.6.0-alpha.54"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "npm",
        "name": "parse-server"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "8.6.60"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-33624"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-367"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-03-24T19:48:24Z",
    "nvd_published_at": "2026-03-24T19:16:55Z",
    "severity": "LOW"
  },
  "details": "### Impact\n\nAn attacker who obtains a user\u0027s password and a single MFA recovery code can reuse that recovery code an unlimited number of times by sending concurrent login requests. This defeats the single-use design of recovery codes. The attack requires the user\u0027s password, a valid recovery code, and the ability to send concurrent requests within milliseconds.\n\n### Patches\n\nThe login handler now uses optimistic locking when updating auth data that contains consumed single-use tokens. If a concurrent request has already modified the recovery array, the update fails and the login is rejected.\n\n### Workarounds\n\nThere are no known workarounds.",
  "id": "GHSA-2299-ghjr-6vjp",
  "modified": "2026-03-27T21:54:30Z",
  "published": "2026-03-24T19:48:24Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/parse-community/parse-server/security/advisories/GHSA-2299-ghjr-6vjp"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-33624"
    },
    {
      "type": "WEB",
      "url": "https://github.com/parse-community/parse-server/pull/10275"
    },
    {
      "type": "WEB",
      "url": "https://github.com/parse-community/parse-server/pull/10276"
    },
    {
      "type": "WEB",
      "url": "https://github.com/parse-community/parse-server/commit/5e70094250a36bfcc14ecd49592be2b94fba66ff"
    },
    {
      "type": "WEB",
      "url": "https://github.com/parse-community/parse-server/commit/fc3da35a81d5083b453e8967cabcc880f1a3bd0c"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/parse-community/parse-server"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:H/AT:P/PR:H/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Parse Server: MFA recovery code single-use bypass via concurrent requests"
}

CVE-2026-33624 (GCVE-0-2026-33624)

Vulnerability from cvelistv5 – Published: 2026-03-24 18:28 – Updated: 2026-03-25 14:28

Title

Parse Server: MFA recovery code single-use bypass via concurrent requests

Summary

Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.60 and 9.6.0-alpha.54, an attacker who obtains a user's password and a single MFA recovery code can reuse that recovery code an unlimited number of times by sending concurrent login requests. This defeats the single-use design of recovery codes. The attack requires the user's password, a valid recovery code, and the ability to send concurrent requests within milliseconds. This issue has been patched in versions 8.6.60 and 9.6.0-alpha.54.

Severity

2.1 (Low)


                        
                          CVSS:4.0/AV:N/AC:H/AT:P/PR:H/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-03-25 13:58 UTC

CWE

CWE-367 - Time-of-check Time-of-use (TOCTOU) Race Condition

Assigner

GitHub_M mitre root

References

5 references

URL	Tags
https://github.com/parse-community/parse-server/s…	x_refsource_CONFIRM
https://github.com/parse-community/parse-server/p…	x_refsource_MISC
https://github.com/parse-community/parse-server/p…	x_refsource_MISC
https://github.com/parse-community/parse-server/c…	x_refsource_MISC
https://github.com/parse-community/parse-server/c…	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version
parse-community	parse-server	Affected: < 8.6.60 Affected: >= 9.0.0, < 9.6.0-alpha.54

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-33624",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-03-25T13:58:24.106962Z",
                "version": "2.0.3"
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        "providerMetadata": {
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          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
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          "product": "parse-server",
          "vendor": "parse-community",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 8.6.60"
            },
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              "status": "affected",
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        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "attackComplexity": "HIGH",
            "attackRequirements": "PRESENT",
            "attackVector": "NETWORK",
            "baseScore": 2.1,
            "baseSeverity": "LOW",
            "privilegesRequired": "HIGH",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "NONE",
            "vectorString": "CVSS:4.0/AV:N/AC:H/AT:P/PR:H/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "NONE",
            "vulnConfidentialityImpact": "NONE",
            "vulnIntegrityImpact": "LOW"
          }
        }
      ],
      "problemTypes": [
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              "cweId": "CWE-367",
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      "providerMetadata": {
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      "references": [
        {
          "name": "https://github.com/parse-community/parse-server/security/advisories/GHSA-2299-ghjr-6vjp",
          "tags": [
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          "url": "https://github.com/parse-community/parse-server/security/advisories/GHSA-2299-ghjr-6vjp"
        },
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      "source": {
        "advisory": "GHSA-2299-ghjr-6vjp",
        "discovery": "UNKNOWN"
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      "title": "Parse Server: MFA recovery code single-use bypass via concurrent requests"
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  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
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    "dateReserved": "2026-03-23T14:24:11.617Z",
    "dateUpdated": "2026-03-25T14:28:24.585Z",
    "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.

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.