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Common Weakness Enumeration

CWE-204

Allowed

Observable Response Discrepancy

Abstraction: Base · Status: Incomplete

The product provides different responses to incoming requests in a way that reveals internal state information to an unauthorized actor outside of the intended control sphere.

341 vulnerabilities reference this CWE, most recent first.

GHSA-6X5V-CXPP-PC5X

Vulnerability from github – Published: 2023-03-21 06:30 – Updated: 2023-03-23 19:10
VLAI
Summary
Answer has Observable Response Discrepancy
Details

Observable Response Discrepancy in GitHub repository answerdev/answer prior to 1.0.6.

Show details on source website

{
  "affected": [
    {
      "package": {
        "ecosystem": "Go",
        "name": "github.com/answerdev/answer"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.0.6"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2023-1540"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-203",
      "CWE-204"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2023-03-21T22:32:37Z",
    "nvd_published_at": "2023-03-21T05:15:00Z",
    "severity": "MODERATE"
  },
  "details": "Observable Response Discrepancy in GitHub repository answerdev/answer prior to 1.0.6.",
  "id": "GHSA-6x5v-cxpp-pc5x",
  "modified": "2023-03-23T19:10:59Z",
  "published": "2023-03-21T06:30:17Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2023-1540"
    },
    {
      "type": "WEB",
      "url": "https://github.com/answerdev/answer/commit/1de3ec27e50ba7389c9449c59e8ea3a37a908ee4"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/answerdev/answer"
    },
    {
      "type": "WEB",
      "url": "https://huntr.dev/bounties/d8d6c259-a0f2-4209-a3b0-ecbf3eb092f4"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Answer has Observable Response Discrepancy"
}

GHSA-6XFP-3HVW-2Q77

Vulnerability from github – Published: 2026-09-04 15:36 – Updated: 2026-09-04 15:36
VLAI
Details

Observable response discrepancy vulnerability in GastroMenum GastroMenum Web Panel allows Account Footprinting.

This issue affects GastroMenum Web Panel: before 31.08.2026.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2026-19205"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-204"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-09-04T15:17:33Z",
    "severity": "HIGH"
  },
  "details": "Observable response discrepancy vulnerability in GastroMenum GastroMenum Web Panel allows Account Footprinting.\n\nThis issue affects GastroMenum Web Panel: before 31.08.2026.",
  "id": "GHSA-6xfp-3hvw-2q77",
  "modified": "2026-09-04T15:36:12Z",
  "published": "2026-09-04T15:36:12Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-19205"
    },
    {
      "type": "WEB",
      "url": "https://siberguvenlik.gov.tr/guvenlik-bildirimleri/detay/tr-26-1013"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-742G-XJV2-HVH9

Vulnerability from github – Published: 2026-02-20 00:31 – Updated: 2026-02-24 18:31
VLAI
Details

A user enumeration vulnerability exists in FormaLMS 4.1.18 and below in the password recovery functionality accessible via the /lostpwd endpoint. The application returns different error messages for valid and invalid usernames allowing an unauthenticated attacker to determine which usernames are registered in the system through observable response discrepancy.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2026-26744"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-204"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-02-19T22:16:47Z",
    "severity": "MODERATE"
  },
  "details": "A user enumeration vulnerability exists in FormaLMS 4.1.18 and below in the password recovery functionality accessible via the /lostpwd endpoint. The application returns different error messages for valid and invalid usernames allowing an unauthenticated attacker to determine which usernames are registered in the system through observable response discrepancy.",
  "id": "GHSA-742g-xjv2-hvh9",
  "modified": "2026-02-24T18:31:00Z",
  "published": "2026-02-20T00:31:53Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-26744"
    },
    {
      "type": "WEB",
      "url": "https://github.com/formalms/formalms.git"
    },
    {
      "type": "WEB",
      "url": "https://github.com/lorenzobruno7/CVE-2026-26744"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-747X-F8JR-J7M2

Vulnerability from github – Published: 2024-07-04 15:30 – Updated: 2024-08-22 21:31
VLAI
Details

Kaiten 57.128.8 allows remote attackers to enumerate user accounts via a crafted POST request, because a login response contains a user_email field only if the user account exists.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2024-39211"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-204"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2024-07-04T13:15:10Z",
    "severity": "MODERATE"
  },
  "details": "Kaiten 57.128.8 allows remote attackers to enumerate user accounts via a crafted POST request, because a login response contains a user_email field only if the user account exists.",
  "id": "GHSA-747x-f8jr-j7m2",
  "modified": "2024-08-22T21:31:28Z",
  "published": "2024-07-04T15:30:40Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2024-39211"
    },
    {
      "type": "WEB",
      "url": "https://github.com/artemy-ccrsky/CVE-2024-39211"
    },
    {
      "type": "WEB",
      "url": "https://github.com/artemy-ccrsky/CVE-2024-39211/blob/main/CVE-2024-39211.sh"
    },
    {
      "type": "WEB",
      "url": "https://kaiten.ru"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-76XR-V7HF-HJJ2

Vulnerability from github – Published: 2026-09-11 09:31 – Updated: 2026-09-11 09:31
VLAI
Details

Smart Video Intercom System developed by Kingdom Communication Associated has a Sensitive Data Exposure vulnerability. Unauthenticated remote attackers can enumerate valid user accounts by exploiting differences in system responses.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2026-89173"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-204"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-09-11T08:16:48Z",
    "severity": "MODERATE"
  },
  "details": "Smart Video Intercom System developed by Kingdom Communication Associated has a Sensitive Data Exposure vulnerability. Unauthenticated remote attackers can enumerate valid user accounts by exploiting differences in system responses.",
  "id": "GHSA-76xr-v7hf-hjj2",
  "modified": "2026-09-11T09:31:23Z",
  "published": "2026-09-11T09:31:23Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-89173"
    },
    {
      "type": "WEB",
      "url": "https://www.twcert.org.tw/en/cp-139-11199-38e1e-2.html"
    },
    {
      "type": "WEB",
      "url": "https://www.twcert.org.tw/tw/cp-132-11198-b8bba-1.html"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/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"
    }
  ]
}

GHSA-78G4-C5R9-6GH7

Vulnerability from github – Published: 2023-07-05 12:30 – Updated: 2024-04-04 05:23
VLAI
Details

TN-5900 Series version 3.3 and prior versions is vulnearble to user enumeration vulnerability. The vulnerability may allow a remote attacker to determine whether a user is valid during password recovery through the web login page and enable a brute force attack with valid users.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2023-3336"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-203",
      "CWE-204"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2023-07-05T10:15:10Z",
    "severity": "MODERATE"
  },
  "details": "TN-5900 Series version 3.3 and prior versions is vulnearble to user enumeration vulnerability. The vulnerability may allow a remote attacker to determine whether a user is valid during password recovery through the web login page and enable a brute force attack with valid users.\n\n",
  "id": "GHSA-78g4-c5r9-6gh7",
  "modified": "2024-04-04T05:23:23Z",
  "published": "2023-07-05T12:30:15Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2023-3336"
    },
    {
      "type": "WEB",
      "url": "https://www.moxa.com/en/support/product-support/security-advisory/mpsa-230401-tn-5900-series-user-enumeration-vulnerability"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-7C2M-F7CW-58XJ

Vulnerability from github – Published: 2023-04-11 12:30 – Updated: 2023-04-11 12:30
VLAI
Details

A vulnerability has been identified in Mendix Forgot Password (Mendix 7 compatible) (All versions < V3.7.1), Mendix Forgot Password (Mendix 8 compatible) (All versions < V4.1.1), Mendix Forgot Password (Mendix 9 compatible) (All versions < V5.1.1). The affected versions of the module contain an observable response discrepancy issue that could allow an attacker to retrieve sensitive information.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2023-27464"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-203",
      "CWE-204"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2023-04-11T10:15:00Z",
    "severity": "MODERATE"
  },
  "details": "A vulnerability has been identified in Mendix Forgot Password (Mendix 7 compatible) (All versions \u003c V3.7.1), Mendix Forgot Password (Mendix 8 compatible) (All versions \u003c V4.1.1), Mendix Forgot Password (Mendix 9 compatible) (All versions \u003c V5.1.1). The affected versions of the module contain an observable response discrepancy issue that could allow an attacker to retrieve sensitive information.",
  "id": "GHSA-7c2m-f7cw-58xj",
  "modified": "2023-04-11T12:30:26Z",
  "published": "2023-04-11T12:30:26Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2023-27464"
    },
    {
      "type": "WEB",
      "url": "https://cert-portal.siemens.com/productcert/pdf/ssa-699404.pdf"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-7H2G-P6HQ-VH75

Vulnerability from github – Published: 2026-04-01 18:36 – Updated: 2026-04-01 18:36
VLAI
Details

The login mechanism of Sage DPW 2021_06_004 displays distinct responses for valid and invalid usernames, allowing enumeration of existing accounts in versions before 2021_06_000. On-premise administrators can toggle this behavior in newer versions.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2025-67806"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-203",
      "CWE-204"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-04-01T16:23:48Z",
    "severity": "LOW"
  },
  "details": "The login mechanism of Sage DPW 2021_06_004 displays distinct responses for valid and invalid usernames, allowing enumeration of existing accounts in versions before 2021_06_000. On-premise administrators can toggle this behavior in newer versions.",
  "id": "GHSA-7h2g-p6hq-vh75",
  "modified": "2026-04-01T18:36:36Z",
  "published": "2026-04-01T18:36:36Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-67806"
    },
    {
      "type": "WEB",
      "url": "https://pastebin.com/Tk4LgMG2"
    },
    {
      "type": "WEB",
      "url": "https://www.sagedpw.at"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-7M4J-QX5P-343W

Vulnerability from github – Published: 2026-07-16 21:30 – Updated: 2026-07-16 21:30
VLAI
Details

An issue was discovered in cyrus-imapd in Cyrus IMAP through 3.12.2. There is an ESEARCH cross-user content oracle. By using the ESEARCH command, an authenticated IMAP user could enumerate folder names under any account they could name. Search would return UIDs of messages matching the search, creating a content oracle (without allowing arbitrary reads of the target's content).

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2026-47083"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-204"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-07-16T19:16:48Z",
    "severity": "MODERATE"
  },
  "details": "An issue was discovered in cyrus-imapd in Cyrus IMAP through 3.12.2. There is an ESEARCH cross-user content oracle. By using the ESEARCH command, an authenticated IMAP user could enumerate folder names under any account they could name. Search would return UIDs of messages matching the search, creating a content oracle (without allowing arbitrary reads of the target\u0027s content).",
  "id": "GHSA-7m4j-qx5p-343w",
  "modified": "2026-07-16T21:30:35Z",
  "published": "2026-07-16T21:30:35Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-47083"
    },
    {
      "type": "WEB",
      "url": "https://www.cyrusimap.org/3.12/imap/download/release-notes/3.12/x/3.12.3.html"
    },
    {
      "type": "WEB",
      "url": "https://www.cyrusimap.org/imap/download/release-notes/index.html"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-7W82-8H79-M4WP

Vulnerability from github – Published: 2024-06-17 18:31 – Updated: 2024-11-18 16:26
VLAI
Details

A vulnerability was found in nasirkhan Laravel Starter up to 11.8.0. It has been rated as problematic. Affected by this issue is some unknown functionality of the file /forgot-password of the component Password Reset Handler. The manipulation of the argument Email leads to observable response discrepancy. The attack may be launched remotely. The complexity of an attack is rather high. The exploitation is known to be difficult. The exploit has been disclosed to the public and may be used. The identifier of this vulnerability is VDB-268784. NOTE: The vendor was contacted early about this disclosure but did not respond in any way.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2024-6056"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-203",
      "CWE-204"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2024-06-17T18:15:18Z",
    "severity": "MODERATE"
  },
  "details": "A vulnerability was found in nasirkhan Laravel Starter up to 11.8.0. It has been rated as problematic. Affected by this issue is some unknown functionality of the file /forgot-password of the component Password Reset Handler. The manipulation of the argument Email leads to observable response discrepancy. The attack may be launched remotely. The complexity of an attack is rather high. The exploitation is known to be difficult. The exploit has been disclosed to the public and may be used. The identifier of this vulnerability is VDB-268784. NOTE: The vendor was contacted early about this disclosure but did not respond in any way.",
  "id": "GHSA-7w82-8h79-m4wp",
  "modified": "2024-11-18T16:26:44Z",
  "published": "2024-06-17T18:31:35Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2024-6056"
    },
    {
      "type": "WEB",
      "url": "https://powerful-bulb-c36.notion.site/idor-c6eb58e8fc40416ba53c7915ca0174c4?pvs=4"
    },
    {
      "type": "WEB",
      "url": "https://vuldb.com/?ctiid.268784"
    },
    {
      "type": "WEB",
      "url": "https://vuldb.com/?id.268784"
    },
    {
      "type": "WEB",
      "url": "https://vuldb.com/?submit.352978"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:N/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"
    }
  ]
}

Mitigation MIT-46
Architecture and Design

Strategy: Separation of Privilege

  • Compartmentalize the system to have "safe" areas where trust boundaries can be unambiguously drawn. Do not allow sensitive data to go outside of the trust boundary and always be careful when interfacing with a compartment outside of the safe area.
  • Ensure that appropriate compartmentalization is built into the system design, and the compartmentalization allows for and reinforces privilege separation functionality. Architects and designers should rely on the principle of least privilege to decide the appropriate time to use privileges and the time to drop privileges.
Mitigation MIT-39
Implementation
  • Ensure that error messages only contain minimal details that are useful to the intended audience and no one else. The messages need to strike the balance between being too cryptic (which can confuse users) or being too detailed (which may reveal more than intended). The messages should not reveal the methods that were used to determine the error. Attackers can use detailed information to refine or optimize their original attack, thereby increasing their chances of success.
  • If errors must be captured in some detail, record them in log messages, but consider what could occur if the log messages can be viewed by attackers. Highly sensitive information such as passwords should never be saved to log files.
  • Avoid inconsistent messaging that might accidentally tip off an attacker about internal state, such as whether a user account exists or not.
CAPEC-331: ICMP IP Total Length Field Probe

An adversary sends a UDP packet to a closed port on the target machine to solicit an IP Header's total length field value within the echoed 'Port Unreachable" error message. This type of behavior is useful for building a signature-base of operating system responses, particularly when error messages contain other types of information that is useful identifying specific operating system responses.

CAPEC-332: ICMP IP 'ID' Field Error Message Probe

An adversary sends a UDP datagram having an assigned value to its internet identification field (ID) to a closed port on a target to observe the manner in which this bit is echoed back in the ICMP error message. This allows the attacker to construct a fingerprint of specific OS behaviors.

CAPEC-541: Application Fingerprinting

An adversary engages in fingerprinting activities to determine the type or version of an application installed on a remote target.

CAPEC-580: System Footprinting

An adversary engages in active probing and exploration activities to determine security information about a remote target system. Often times adversaries will rely on remote applications that can be probed for system configurations.