How severe is CVE-2026-29204?

CVE-2026-29204 has a CVSS 3.x base score of 9.1, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.

Is CVE-2026-29204 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (24th percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2026-29204?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

Does CVE-2026-29204 have an EU (EUVD) identifier?

Yes. CVE-2026-29204 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-29551.

When was CVE-2026-29204 published?

CVE-2026-29204 was published on 2026-05-12 and last updated on 2026-06-17.

CVE-2026-29204

CVE-2026-29204 is a critical-severity vulnerability with a CVSS 3.x base score of 9.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-639.

Key facts

Severity: Critical (CVSS 3.x base score 9.1)
EPSS exploit prediction: 0% (24th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-29551
Weakness: CWE-639
Published: 2026-05-12
Last modified: 2026-06-17

Description

Insufficient ownership check in `clientarea.php` allows an authenticated client area user to submit requests using another user’s `addonId` without any ownership validation leading to unauthorized access to the victim's account.

Frequently asked questions

What is CVE-2026-29204?: Insufficient ownership check in `clientarea.php` allows an authenticated client area user to submit requests using another user’s `addonId` without any ownership validation leading to unauthorized access to the victim's account.
How severe is CVE-2026-29204?: CVE-2026-29204 has a CVSS 3.x base score of 9.1, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.
Is CVE-2026-29204 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (24th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-29204?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
Does CVE-2026-29204 have an EU (EUVD) identifier?: Yes. CVE-2026-29204 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-29551.
When was CVE-2026-29204 published?: CVE-2026-29204 was published on 2026-05-12 and last updated on 2026-06-17.

References

https://help.whmcs.com/m/125386/l/2073908-cve-2026-29204

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