Vulnerability-Lookup

GHSA-MX47-H32C-X878

Vulnerability from github – Published: 2026-06-15 21:30 – Updated: 2026-06-16 12:32

Details

Discuz! X5.0 releases 20260320 through 20260501 contains an authentication bypass vulnerability that allows unauthenticated remote attackers to gain unauthorized access to database backup and restore functionality by exploiting a shared cryptographic key between UCenter integration and the database backup API exposed by dbbak.php. Attackers can inject a crafted payload through the username parameter during login to abuse the encryption oracle in logging_ctl::logging_more(), obtain a legitimately signed token, and use it to bypass authorization for database export and import operations, with the additional ability to trigger a race condition to impersonate arbitrary users.

Severity

9.1 (Critical)


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

9.3 (Critical)


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

Show details on source website

JSON

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{
  "affected": [],
  "aliases": [
    "CVE-2026-49952"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-323"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-06-15T20:16:29Z",
    "severity": "CRITICAL"
  },
  "details": "Discuz! X5.0 releases 20260320 through 20260501 contains an authentication bypass vulnerability that allows unauthenticated remote attackers to gain unauthorized access to database backup and restore functionality by exploiting a shared cryptographic key between UCenter integration and the database backup API exposed by dbbak.php. Attackers can inject a crafted payload through the username parameter during login to abuse the encryption oracle in logging_ctl::logging_more(), obtain a legitimately signed token, and use it to bypass authorization for database export and import operations, with the additional ability to trigger a race condition to impersonate arbitrary users.",
  "id": "GHSA-mx47-h32c-x878",
  "modified": "2026-06-16T12:32:01Z",
  "published": "2026-06-15T21:30:40Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-49952"
    },
    {
      "type": "WEB",
      "url": "https://gitee.com/Discuz/DiscuzX/commit/9962dad52c4c6999dabaf91ecd70377c680ff3c6"
    },
    {
      "type": "WEB",
      "url": "https://karmainsecurity.com/KIS-2026-09"
    },
    {
      "type": "WEB",
      "url": "https://karmainsecurity.com/chaining-bugs-in-discuz-from-race-condition-to-rce"
    },
    {
      "type": "WEB",
      "url": "https://www.vulncheck.com/advisories/discuz-x5-0-authentication-bypass-via-dbbak-php-encryption-oracle"
    },
    {
      "type": "WEB",
      "url": "http://seclists.org/fulldisclosure/2026/Jun/3"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
      "type": "CVSS_V4"
    }
  ]
}

CVE-2026-49952 (GCVE-0-2026-49952)

Vulnerability from cvelistv5 – Published: 2026-06-15 18:43 – Updated: 2026-07-28 01:49 X_Open Source

Title

Discuz! X5.0 Authentication Bypass via dbbak.php Encryption Oracle

Summary

Severity

9.3 (Critical)


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

9.1 (Critical)


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

SSVC

Exploitation: poc Automatable: yes Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-06-15 19:58 UTC

CWE

CWE-323 - Reusing a Nonce, Key Pair in Encryption

Assigner

VulnCheck mitre root

References

5 references

URL	Tags
https://karmainsecurity.com/KIS-2026-09	technical-description
https://karmainsecurity.com/chaining-bugs-in-disc…	exploit
https://gitee.com/Discuz/DiscuzX/commit/9962dad52…	patch
https://www.vulncheck.com/advisories/discuz-x5-0-…	third-party-advisory
http://seclists.org/fulldisclosure/2026/Jun/3

Impacted products

1 product

Vendor	Product	Version
Discuz!	Discuz! X5.0	Affected: 20260320 , ≤ 20260501 (date) cpe:2.3:a:discuz:discuzx::::::::

Date Public

2026-05-09 00:00

Credits

Egidio Romano

Show details on NVD website

JSON

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        "metrics": [
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                "id": "CVE-2026-49952",
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                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-06-15T19:58:52.987295Z",
                "version": "2.0.3"
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          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
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        "providerMetadata": {
          "dateUpdated": "2026-06-16T09:48:23.903Z",
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        "references": [
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          "vendor": "Discuz!",
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              "status": "affected",
              "version": "20260320",
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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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GHSA-MX47-H32C-X878

CVE-2026-49952 (GCVE-0-2026-49952)

Tags

Sightings

Nomenclature

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