Authorization Bypass (IDOR)Weakness · CWE-639

CVE-2026-8839

MEDIUM · 5.3 CVSS v3.1 Published 2026-06-06

Mitigation only

No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.

See remediation →

62/100

Remediation priority · Elevated

Remotely reachable No privileges Zero-click

Official description

NVD · unedited

The MapPress Maps for WordPress plugin for WordPress is vulnerable to Authorization Bypass Through User-Controlled Key in all versions up to, and including, 2.96.6. This is due to missing ownership verification in the REST API routes registered via `Mappress_Api::rest_api_init()`, where the GET `/wp-json/mapp/v1/maps/{mapid}` endpoint uses `'permission_callback' => '__return_true'` and the write endpoints (POST update, DELETE, PATCH mutate, POST clone, POST empty_trash) only check the generic `edit_posts` capability without confirming that the requester owns the targeted map — a gap that is not compensated at the model layer, as `Mappress_Map::get()`, `save()`, `delete()`, `mutate()`, and `empty_trash()` all operate on any caller-supplied map ID without an ownership check. This makes it possible for unauthenticated attackers to read sensitive map data — including POI titles, addresses, coordinates, and body content — for any map on the site by enumerating map IDs, and for authenticated attackers with Contributor-level access and above to modify, delete, trash/restore, or clone any map regardless of its author.

Technical summary

dbcve analysis · high confidence

The MapPress Maps for WordPress plugin has an authorization bypass vulnerability in its REST API. The GET endpoint uses `'permission_callback' => '__return_true'` allowing unauthenticated enumeration of map IDs to read sensitive POI data. All write operations only check for generic `edit_posts` capability without verifying map ownership, enabling authenticated attackers with Contributor+ access to modify, delete, trash, restore, or clone any map on the site.

MitigationUpdate MapPress Maps for WordPress to version 2.96.7 or later, which adds proper ownership verification to REST API permission callbacks. Until then, consider restricting the /wp-json/mapp/ endpoint via server configuration or monitoring for suspicious map ID enumeration.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

CVSS breakdown

From the vector

Attack vector: Network
Complexity: Low
Privileges: None
User interaction: None
Scope: Unchanged
Confidentiality: None
Integrity: Low
Availability: None

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

Am I affected?

dbcve checks

Work through these to decide whether this CVE applies to you.

Verify MapPress Maps plugin is installed

Navigate to WordPress admin dashboard > Plugins and check if 'MapPress Maps' is listed among installed plugins, or use WP-CLI: wp plugin list --name=mappress

Affected if MapPress Maps plugin is active in WordPress installation
Identify installed MapPress version

In WordPress admin > Plugins > MapPress Maps, view the plugin details to see the installed version number, or use: grep -i 'Version:' /path/to/wp-content/plugins/mappress*/readme.txt

Affected if Version cannot be determined or is prior to patched release containing ownership verification
Confirm REST API endpoint exposure

Send a GET request to /wp-json/mapp/v1/maps/1 (or enumerate several IDs) without authentication: curl -s https://TARGET/wp-json/mapp/v1/maps/1

Affected if Request returns map data (POIs, addresses, coordinates) without authentication (HTTP 200 with JSON payload containing map details)
Check permission_callback in REST API registration

Examine the plugin source file that registers REST routes (typically mappress.php or includes/class-rest.php), search for 'permission_callback' => '__return_true' in mapp/v1 routes

Affected if File contains 'permission_callback' => '__return_true' for map endpoints, bypassing authentication
Verify write access for low-privilege users

Authenticate as a Contributor-level user and attempt to modify, delete, or clone a map created by another user via POST/PATCH/DELETE to /wp-json/mapp/v1/maps/{id}

Affected if Operations succeed without ownership verification (map is modified/deleted/cloned despite being owned by a different user)

Your environment is affected if MapPress Maps plugin is installed and the REST API returns map data to unauthenticated users or allows Contributor-level users to modify maps they do not own.

Generated from the published advisory. Verify against your own configuration.

Remediation

dbcve · scoped

Mitigation available No clean upgrade yet — mitigate in the meantime

Mitigation

Update MapPress Maps for WordPress to version 2.96.7 or later, which adds proper ownership verification to REST API permission callbacks. Until then, consider restricting the /wp-json/mapp/ endpoint via server configuration or monitoring for suspicious map ID enumeration.

Recommended fix Moderate confidence

MapPress Maps for WordPress version 2.96.7 or later

1. Navigate to the WordPress admin dashboard
2. Go to Plugins > Installed Plugins
3. Locate 'MapPress Maps for WordPress' in the plugin list
4. If an update is available, click 'Update Now' to upgrade to version 2.96.7 or later
5. If no update is shown in the dashboard, manually download version 2.96.7 or later from the WordPress Plugin Repository at plugins.trac.wordpress.org
6. Deactivate the current plugin, then delete it, and upload/install the new version
7. After upgrading, verify the fix by attempting to access a map via the REST API endpoint `/wp-json/mapp/v1/maps/{mapid}` without proper authentication — this should now be blocked
8. Review map ownership permissions to ensure users can only modify maps they created

Generated from the published advisory — verify against the referenced sources before acting.

Have this fixed Scoped from the published advisory

Consultation2.0 h
Implementation3.0 h
Testing3.0 h
Review / QA2.0 h

10.0 hours of engineering $1,750

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References

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-8839 in production — separate from our analysis above.

Notes0 Guidelines

Know something about CVE-2026-8839?

The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.

The version that genuinely resolved it — not the one the vendor claimed
A config change or rule that shut the vector down
A gotcha in the upgrade path that cost you an afternoon

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here

Verified mitigations, workarounds, and config changes
Version or environment caveats, and links to real fixes
No weaponised exploit code, or anything meant to cause harm
No spam, self-promotion, credentials, or personal data

At a glance

A fix existsA vendor remedy is published

Severity 5.3 Medium

Exploit likelihood EPSS, next 30 days 1.0%

Remediation

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Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

Check your environment

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

Scan for this in your stack

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Practitioner notes

No notes yet

Official description

Technical summary

CVSS breakdown

Am I affected?

Remediation

References