CVE-2026-42070: MantisBT Authorization Bypass Vulnerability

MODERATE
Advisory Identifier: GHSA-pq86-j2c2-47f6
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CWE-863
Published
Advisory Summary

CVE-2026-42070 is a MODERATE authorization bypass vulnerability (CWE-863: Incorrect Authorization) affecting MantisBT libraries in the Packagist ecosystem. The issue involves authorization bypass in bugnote editing via issue update api. Remediation is available by upgrading affected packages to version 2.28.2.

CVE-2026-42070 at a Glance

CVE Identifier CVE-2026-42070
GHSA Identifier GHSA-pq86-j2c2-47f6
Severity MODERATE
CVSS v3.1 Base Score N/A
CWE Classification CWE-863: Incorrect Authorization
Affected Product MantisBT
Package Ecosystem Packagist
Published Date
Last Updated

How to Fix CVE-2026-42070

To remediate this vulnerability, upgrade all affected MantisBT dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

mantisbt/mantisbt fixed: 2.28.2 
Upgrade mantisbt/mantisbt to 2.28.2
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

inspect dependencies for mantisbt/mantisbt

How to Check if You Are Affected

To determine whether your application is affected by CVE-2026-42070, inspect your project dependencies for MantisBT:

inspect dependencies for mantisbt/mantisbt

Analyze the terminal output to locate any version of MantisBT in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 2.28.2), your application is affected.

Note: Verify declared build manifests and deployed runtime container environments.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-863: Incorrect Authorization, where the product performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check. In MantisBT, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

The mc_issue_update() function in MantisBT allows users having *update_bug_threshold* access (UPDATER, with default settings) to edit, change view state, and modify time tracking on bugnotes belonging to other users — bypassing the default DEVELOPER (level 55) threshold required by the dedicated mc_issue_note_update() function. ### Impact 1. UPDATER can edit notes by DEVELOPER/MANAGER/ADMIN — bypassing the DEVELOPER threshold 2. UPDATER can change private notes to public — exposing confidential internal discussion 3. UPDATER can change public notes to private — hiding information from reporters/viewers ### Patches - 6e58fae4f22efdc3987f903c8ba2611de17a9435 ### Workarounds None ### Credits Thanks to the following security researchers for independently discovering and responsibly reporting the issue. - Vishal Shukla - Tristan Madani (@TristanInSec) from Talence Security This advisory's contents was largely copied from Tristan's well-written report.

CVE-2026-42070 Affected MantisBT Versions

1 component(s)
Fixed Versions:
2.28.2
Product / Package Ecosystem Affected Versions Fixed Version
mantisbt/mantisbt
 Packagist
< 2.28.2
2.28.2

References

GitHub Advisory / Wiki ADVISORY
https://github.com/mantisbt/mantisbt/security/advisories/GHSA-pq86-j2c2-47f6
NVD — CVE-2026-42070 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-42070
Security Fix Commit FIX COMMIT
https://github.com/mantisbt/mantisbt/commit/6e58fae4f22efdc3987f903c8ba2611de17a9435
MantisBT Source Repository REPOSITORY
https://github.com/mantisbt/mantisbt
MantisBT Security Information SECURITY
https://mantisbt.org/bugs/view.php?id=37089
MantisBT Security Information SECURITY
https://mantisbt.org/bugs/view.php?id=37093

Frequently Asked Questions

What is CVE-2026-42070?
CVE-2026-42070 is a security vulnerability in MantisBT involving Authorization Bypass in Bugnote Editing via Issue Update API under CWE-863: Incorrect Authorization.
Which MantisBT versions are affected?
Affected versions include releases prior to 2.28.2 across affected packages: mantisbt/mantisbt.
What version fixes CVE-2026-42070?
Upgrading to 2.28.2 (or the latest patched release for your respective branch) resolves the vulnerability.
Is mantisbt/mantisbt affected?
Yes, mantisbt/mantisbt is affected in releases prior to 2.28.2. Upgrade your dependency to 2.28.2 or later.
What CWE is associated with CVE-2026-42070?
CVE-2026-42070 is classified under CWE-863: Incorrect Authorization (The product performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check.).
How can I check Packagist dependencies for CVE-2026-42070?
Run the dependency tree command: 'inspect dependencies for mantisbt/mantisbt'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-pq86-j2c2-47f6",
  "modified" : "2026-06-09T10:23:43Z",
  "published" : "2026-05-11T19:39:31Z",
  "aliases" : [ "CVE-2026-42070" ],
  "summary" : "MantisBT: Authorization Bypass in Bugnote Editing via Issue Update API",
  "details" : "The mc_issue_update() function in MantisBT allows users having *update_bug_threshold* access (UPDATER, with default settings) to edit, change view state, and modify time tracking on bugnotes belonging to other users — bypassing the default DEVELOPER (level 55) threshold required by the dedicated mc_issue_note_update() function.\n\n### Impact\n1. UPDATER can edit notes by DEVELOPER/MANAGER/ADMIN — bypassing the DEVELOPER threshold\n2. UPDATER can change private notes to public — exposing confidential internal discussion\n3. UPDATER can change public notes to private — hiding information from reporters/viewers\n\n### Patches\n- 6e58fae4f22efdc3987f903c8ba2611de17a9435\n\n### Workarounds\nNone\n\n### Credits\nThanks to the following security researchers for independently discovering and responsibly reporting the issue.\n- Vishal Shukla \n- Tristan Madani (@TristanInSec) from Talence Security \n\nThis advisory's contents was largely copied from Tristan's well-written report.",
  "severity" : [ {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Packagist",
      "name" : "mantisbt/mantisbt"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "2.28.2"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 2.28.1"
    }
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/mantisbt/mantisbt/security/advisories/GHSA-pq86-j2c2-47f6"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-42070"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/mantisbt/mantisbt/commit/6e58fae4f22efdc3987f903c8ba2611de17a9435"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/mantisbt/mantisbt"
  }, {
    "type" : "WEB",
    "url" : "https://mantisbt.org/bugs/view.php?id=37089"
  }, {
    "type" : "WEB",
    "url" : "https://mantisbt.org/bugs/view.php?id=37093"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-863" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-05-11T19:39:31Z",
    "nvd_published_at" : "2026-05-28T21:16:29Z"
  }
}