CVE-2026-77035Network attack vector

Cross-user record takeover via forged ownership fields

Published Aug 27, 2026 · Updated Aug 27, 2026

Authorization bypass in JEM before 5.0.1 allows remote authenticated users to take over other users' events and venues via forged form data. The event and venue edit path trusts the submitted record ID and created_by value instead of verifying that the record belongs to the requester. A registered account with edit-own rights through eventowner=1 or core.edit.own is sufficient, and the resulting access is limited to ownership and modification of those records.

CVSS severity5.1
Medium
EPSS probability0.23%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Authorization bypass in JEM before 5.0.1 allows remote authenticated users to take over other users' events and venues via forged form data. The event and venue edit path trusts the submitted record ID and created_by value instead of verifying that the record belongs to the requester. A registered account with edit-own rights through eventowner=1 or core.edit.own is sufficient, and the resulting access is limited to ownership and modification of those records.

The record

CVE
CVE-2026-77035
Published
Aug 27, 2026
Updated
Aug 27, 2026
Vendor
JEM Team
Product
JEM
Classifications
CWE-639
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 27, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 27, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=1.0.0-5.0.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

JEM Team · JEMversion=1.0.0-5.0.0

Published CVSS scores

5.1JoomlaCVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-639Authorization Bypass Through User-Controlled Key

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo