CVE-2026-78006 json
The Events Calendar <= 6.17.4 - Unauthenticated PHP Object Injection to Remote Code Execution
published last mo. modified last mo. also EUVD-2026-76832
- cvss
- 9.8
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.5%
- EPSS 1.5% chance of exploitation in 30 days, percentile 74%
- public exploits
- 0
- none known
Summary
The The Events Calendar plugin for WordPress is vulnerable to Remote Code Execution in all versions up to, and including, 6.17.4 via the is_safe_widget_instance function. This is due to insufficient protection in is_safe_widget_instance, which can be bypassed because PHP fires magic methods during its pre-parse, combined with enable_rendering_widget_copied() forging a valid wp_hash integrity attribute before unserialize() is reached. This makes it possible for unauthenticated attackers to execute code on the server. This is exploitable without authentication or approval because the plugin's V2 single-event template runs do_blocks() over buffered comment HTML, and WordPress returns a moderation-hash URL that allows an unauthenticated commenter to immediately view their own pending comment, delivering the injected block markup to the vulnerable code path before any moderation occurs. This does require comments to be enabled and visible on events.
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Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- total
- Assessed
- last mo.
Exploit prediction
1.47% chance of exploitation in the next 30 days, higher than 74% of all scored CVEs (FIRST EPSS, 2026-11-11).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
Affected products
- stellarwp The Events Calendar
Classification
- Weakness
-
- CWE-502 Deserialization of Untrusted Data
- Technology feeds
References
- wordfence.com /threat-intel/vulnerabilities/id/a0c67346-534a-4b67-a904-fa148703707a?source=cve
- plugins.trac.wordpress.org /browser/the-events-calendar/tags/6.17.3/src/Tribe/Views/V2/Template_Bootstrap.php#L213
- plugins.trac.wordpress.org /browser/the-events-calendar/tags/6.17.3/src/Tribe/Views/V2/Widgets/Service_Provider.php#L295
- plugins.trac.wordpress.org /browser/the-events-calendar/tags/6.17.3/src/Tribe/Views/V2/Widgets/Service_Provider.php#L255
- plugins.trac.wordpress.org /browser/the-events-calendar/tags/6.17.3/src/Tribe/Collections/Lazy_Post_Collection.php#L82
- plugins.trac.wordpress.org /browser/the-events-calendar/tags/6.17.3/common/src/Tribe/Utils/Collection_Trait.php#L247
- plugins.trac.wordpress.org /changeset?reponame=&old=3690576%40the-events-calendar&new=3690576%40the-events-calendar
Sources
- CVE List CVE-2026-78006
- NVD CVE-2026-78006
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