CVE-2026-53673 is a high-severity (CVSS 8.1) CWE-639 vulnerability in buddypress/buddypress. A fix is available for buddypress/buddypress — see the affected versions and patch details below.
BuddyPress: Authenticated attackers can access arbitrary private message threads via user_id request parameter
Exploitation Status
No confirmed exploitation observed yet
- A successful exploit gives an attacker total control of the affected component, not partial access.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-53673.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
CVE-2026-53673 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.
Where this sits among everything scored
Of 379,842 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.
Real-World Exposure
buddypress/buddypressReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.
Description
BuddyPress 14.4.0 contains an insecure direct object reference vulnerability in the messages REST API that allows authenticated attackers to access arbitrary private message threads by supplying a user_id parameter in the request. Attackers can pass another user's identifier to the get_item_permissions_check method, which validates the supplied user_id instead of the logged-in user and is reused by the update and delete handlers, to read, reply to, or delete any user's private messages.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | buddypress/buddypress | all versions | 14.5.0composer require buddypress/buddypress:^14.5.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for buddypress/buddypress, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update buddypress/buddypress to 14.5.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-53673 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
Frequently Asked Questions
Is CVE-2026-53673 in your dependencies?
Find it across Packagist, including transitive dependencies.