{"id":"CVE-2026-33541","aliases":["EUVD-2026-16398","GHSA-f346-8rp3-4h9h"],"status":"published","title":"TSPortal's Uncontrolled User Creation via Validation Side Effects Leads to Potential Denial of Service","description":"TSPortal is the WikiTide Foundation’s in-house platform used by the Trust and Safety team to manage reports, investigations, appeals, and transparency work. Prior to version 34, a flaw in TSPortal allowed attackers to create arbitrary user records in the database by abusing validation logic. While validation correctly rejected invalid usernames, a side effect within a validation rule caused user records to be created regardless of whether the request succeeded. This could be exploited to cause uncontrolled database growth, leading to a potential denial of service (DoS). Version 34 contains a fix for the issue.","severity":{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.00304,"percentile":0.23456,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-400","CWE-770"],"published":"2026-03-26T20:27:05Z","modified":"2026-10-28T02:30:28Z","fixes":[{"ecosystem":"Packagist","package":"miraheze/ts-portal","fixed_in":["34"],"sources":["ghsa","osv"]}],"affected":[{"source":"ghsa","ecosystem":"Packagist","package":"miraheze/ts-portal","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"33"},{"fixed":"34"}]}]},{"source":"osv","ecosystem":"Packagist","package":"miraheze/ts-portal","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"34"}]}],"versions":["v1","v10","v11","v12","v13","v14","v15","v16","v17","v18","v19","v2","v20","v21","v22","v23","v24","v25","v26","v27","v28","v29","v3","v30","v31","v32","v33","v4","v5","v6","v7","v8","v9"]}],"products":[{"vendor":"miraheze","product":"tsportal"},{"vendor":"wikitide","product":"tsportal"}],"references":[{"url":"https://github.com/miraheze/TSPortal/security/advisories/GHSA-f346-8rp3-4h9h","tags":["x_refsource_CONFIRM","Exploit","Mitigation","Vendor Advisory","advisory","web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-33541","tags":["advisory"]},{"url":"https://issue-tracker.miraheze.org/T15115","tags":["web"]},{"url":"https://github.com/advisories/GHSA-f346-8rp3-4h9h"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/33xxx/CVE-2026-33541.json","tags":["advisory"]},{"url":"https://github.com/miraheze/TSPortal","tags":["package"]}],"sources":{"cve":[{"id":"CVE-2026-33541","title":"TSPortal's Uncontrolled User Creation via Validation Side Effects Leads to Potential Denial of Service","description":"TSPortal is the WikiTide Foundation’s in-house platform used by the Trust and Safety team to manage reports, investigations, appeals, and transparency work. Prior to version 34, a flaw in TSPortal allowed attackers to create arbitrary user records in the database by abusing validation logic. While validation correctly rejected invalid usernames, a side effect within a validation rule caused user records to be created regardless of whether the request succeeded. This could be exploited to cause uncontrolled database growth, leading to a potential denial of service (DoS). Version 34 contains a fix for the issue.","status":"published","published":"2026-03-26T20:27:05.84Z","modified":"2026-03-27T20:01:35.174Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","level":"medium","assessor":"cna"}],"cwes":["CWE-400","CWE-770"],"updated_at":"2026-11-02T14:20:07.609948Z"}],"euvd":[{"id":"EUVD-2026-16398","description":"TSPortal is the WikiTide Foundation’s in-house platform used by the Trust and Safety team to manage reports, investigations, appeals, and transparency work. Prior to version 34, a flaw in TSPortal allowed attackers to create arbitrary user records in the database by abusing validation logic. While validation correctly rejected invalid usernames, a side effect within a validation rule caused user records to be created regardless of whether the request succeeded. This could be exploited to cause uncontrolled database growth, leading to a potential denial of service (DoS). Version 34 contains a fix for the issue.","status":"published","published":"2026-03-26T20:27:05Z","modified":"2026-03-27T20:01:35Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","level":"medium"}],"updated_at":"2026-11-02T19:25:26.783049Z"}],"ghsa":[{"id":"GHSA-f346-8rp3-4h9h","title":"TSPortal's Uncontrolled User Creation via Validation Side Effects Leads to Potential Denial of Service","description":"### Summary\nA flaw in TSPortal allowed attackers to create arbitrary user records in the database by abusing validation logic. While validation correctly rejected invalid usernames, a side effect within a validation rule caused user records to be created regardless of whether the request succeeded. This could be exploited to cause uncontrolled database growth, leading to a potential denial of service (DoS).\n\n### Details\nWhen submitting a Data Processing Agreement (DPA) request in TSPortal, the `DPAAlreadyLive` validation rule previously called `User::findOrCreate()`.\n\nThis method created a user record if one did not already exist.\n\nAlthough username validation (via `MirahezeUsernameRule`) correctly rejected invalid usernames, the `DPAAlreadyLive` rule was still executed during validation. Because it performed a state-changing operation, it created user records even when the overall validation failed and no DPA was created.\n\nAs a result:\n- Validation correctly rejected invalid input\n- However, user records were still inserted into the database as a side effect\n\nThese records were created:\n- Without a successful DPA request\n- Without audit logging tied to a completed action\n- Without visibility into their origin\n\n### Impact\nAn attacker could exploit this behavior by automating requests with invalid usernames, resulting in:\n\n- Mass creation of arbitrary user records\n- Unbounded database growth\n- Increased storage and indexing overhead\n- Potential degradation of application performance\n\nAt scale, this could lead to a denial of service condition due to resource exhaustion.\n\n### Proof of Concept\n1. Submit a DPA request using an invalid username\n2. Ensure the request fails validation due to `MirahezeUsernameRule`\n3. Observe that a corresponding user record is still created in the database\n\nThis behavior was confirmed prior to remediation.\n\n### Root Cause\nThe issue stemmed from:\n- Performing state-changing operations (`findOrCreate`) inside validation logic\n- Validation rules executing regardless of overall validation success\n- Lack of separation between validation and persistence layers\n\n### Mitigation\nThe issue has been fixed by removing database write operations from validation logic.\n\nSpecifically:\n- Replaced `User::findOrCreate()` with a non-mutating lookup (`User::firstWhere(...)`)\n- Ensured validation rules only perform read operations\n- Prevented user creation unless all validation passes","status":"published","published":"2026-03-27T15:42:20Z","modified":"2026-03-27T15:42:23Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","level":"medium"}],"cwes":["CWE-400","CWE-770"],"updated_at":"2026-11-02T14:39:43.747579Z"}],"nvd":[{"id":"CVE-2026-33541","description":"TSPortal is the WikiTide Foundation’s in-house platform used by the Trust and Safety team to manage reports, investigations, appeals, and transparency work. Prior to version 34, a flaw in TSPortal allowed attackers to create arbitrary user records in the database by abusing validation logic. While validation correctly rejected invalid usernames, a side effect within a validation rule caused user records to be created regardless of whether the request succeeded. This could be exploited to cause uncontrolled database growth, leading to a potential denial of service (DoS). Version 34 contains a fix for the issue.","status":"published","published":"2026-03-26T21:17:05.867Z","modified":"2026-06-17T10:37:40.89Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","level":"medium","assessor":"secondary"}],"cwes":["CWE-400","CWE-770"],"updated_at":"2026-11-02T14:12:11.678711Z"}],"osv":[{"id":"CVE-2026-33541","title":"TSPortal's Uncontrolled User Creation via Validation Side Effects Leads to Potential Denial of Service","description":"TSPortal is the WikiTide Foundation’s in-house platform used by the Trust and Safety team to manage reports, investigations, appeals, and transparency work. Prior to version 34, a flaw in TSPortal allowed attackers to create arbitrary user records in the database by abusing validation logic. While validation correctly rejected invalid usernames, a side effect within a validation rule caused user records to be created regardless of whether the request succeeded. This could be exploited to cause uncontrolled database growth, leading to a potential denial of service (DoS). Version 34 contains a fix for the issue.","status":"published","published":"2026-03-26T20:27:05.84Z","modified":"2026-10-28T02:30:28.203848833Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","level":"medium"}],"cwes":["CWE-400","CWE-770"],"updated_at":"2026-11-02T15:45:01.896044Z"},{"id":"GHSA-f346-8rp3-4h9h","title":"TSPortal's Uncontrolled User Creation via Validation Side Effects Leads to Potential Denial of Service","description":"### Summary\nA flaw in TSPortal allowed attackers to create arbitrary user records in the database by abusing validation logic. While validation correctly rejected invalid usernames, a side effect within a validation rule caused user records to be created regardless of whether the request succeeded. This could be exploited to cause uncontrolled database growth, leading to a potential denial of service (DoS).\n\n### Details\nWhen submitting a Data Processing Agreement (DPA) request in TSPortal, the `DPAAlreadyLive` validation rule previously called `User::findOrCreate()`.\n\nThis method created a user record if one did not already exist.\n\nAlthough username validation (via `MirahezeUsernameRule`) correctly rejected invalid usernames, the `DPAAlreadyLive` rule was still executed during validation. Because it performed a state-changing operation, it created user records even when the overall validation failed and no DPA was created.\n\nAs a result:\n- Validation correctly rejected invalid input\n- However, user records were still inserted into the database as a side effect\n\nThese records were created:\n- Without a successful DPA request\n- Without audit logging tied to a completed action\n- Without visibility into their origin\n\n### Impact\nAn attacker could exploit this behavior by automating requests with invalid usernames, resulting in:\n\n- Mass creation of arbitrary user records\n- Unbounded database growth\n- Increased storage and indexing overhead\n- Potential degradation of application performance\n\nAt scale, this could lead to a denial of service condition due to resource exhaustion.\n\n### Proof of Concept\n1. Submit a DPA request using an invalid username\n2. Ensure the request fails validation due to `MirahezeUsernameRule`\n3. Observe that a corresponding user record is still created in the database\n\nThis behavior was confirmed prior to remediation.\n\n### Root Cause\nThe issue stemmed from:\n- Performing state-changing operations (`findOrCreate`) inside validation logic\n- Validation rules executing regardless of overall validation success\n- Lack of separation between validation and persistence layers\n\n### Mitigation\nThe issue has been fixed by removing database write operations from validation logic.\n\nSpecifically:\n- Replaced `User::findOrCreate()` with a non-mutating lookup (`User::firstWhere(...)`)\n- Ensured validation rules only perform read operations\n- Prevented user creation unless all validation passes","status":"published","published":"2026-03-27T15:42:20Z","modified":"2026-03-27T16:12:05.202203Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","level":"medium"}],"cwes":["CWE-400","CWE-770"],"updated_at":"2026-11-02T15:46:45.639885Z"}]}}