CVE-2026-1655 | EventPrime <= 4.2.8.4 - Missing Authorization to Authenticated (Subscriber+) Arbitrary Event Modification via 'event_id' Parameter

The EventPrime plugin for WordPress is vulnerable to unauthorized post modification due to missing authorization checks in all versions up to, and including, 4.2.8.4. This is due to the save_frontend_event_submission function accepting a user-controlled event_id parameter and updating the corresponding event post without enforcing ownership or capability checks. This makes it possible for authenticated (Customer+) attackers to modify posts created by administrators by manipulating the event_id parameter granted they can obtain a valid nonce.

Published: 2026-02-18 Last update: 2026-04-15 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2026-1655 is rated Low Risk (17.6/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.01%). Mandatory action: Low composite risk—no urgent action required; patch on your normal maintenance cycle and revisit priority if CVSS or EPSS increases.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-1655

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-02-18 0.01%

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-1655

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
4.3 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
2.8 1.4 [email protected]

Weakness enumeration for CVE-2026-1655

Affected software / configurations for CVE-2026-1655

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2026-1655

URL Tags
https://plugins.trac.wordpress.org/browser/eventprime-event-calendar-management/tags/4.2.8.1/includes/class-ep-ajax.php#L741
https://plugins.trac.wordpress.org/browser/eventprime-event-calendar-management/tags/4.2.8.1/includes/class-ep-ajax.php#L798
https://plugins.trac.wordpress.org/browser/eventprime-event-calendar-management/trunk/includes/class-ep-ajax.php#L741
https://plugins.trac.wordpress.org/browser/eventprime-event-calendar-management/trunk/includes/class-ep-ajax.php#L798
https://plugins.trac.wordpress.org/changeset?sfp_email=&sfph_mail=&reponame=&new=3455239%40eventprime-event-calendar-management%2Ftrunk&old=3452796%40eventprime-event-calendar-management%2Ftrunk&sfp_email=&sfph_mail=
https://www.wordfence.com/threat-intel/vulnerabilities/id/0e2a2769-1309-4aad-8411-4445efea2b66?source=cve
cvelogic Threat Intelligence