CVE-2017-20206 json
Appointments <= 2.2.1 - Unauthenticated PHP Object Injection
published 2025-10-18 12 mo ago modified 2026-06-17 4 mo ago also EUVD-2017-18924
- cvss
- 9.8
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.7%
- EPSS 0.7% chance of exploitation in 30 days, percentile 54%
- public exploits
- 0
- none known
Summary
The Appointments plugin for WordPress is vulnerable to PHP Object Injection in versions up to, and including, 2.2.1 via deserialization of untrusted input from the `wpmudev_appointments` cookie. This allows unauthenticated attackers to inject a PHP Object. Attackers were actively exploiting this vulnerability with the WP_Theme() class to create backdoors.
Patch / fix
CISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- total
- Assessed
- 12 mo ago
Exploit prediction
0.73% chance of exploitation in the next 30 days, higher than 54% of all scored CVEs (FIRST EPSS, 2026-11-08).
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
- wpmudev Appointments
Classification
- Weakness
-
- CWE-502 Deserialization of Untrusted Data
- Technology feeds
References
-
plugins.trac.wordpress.org
/changeset/1733186/appointments
patch
-
wordfence.com
/threat-intel/vulnerabilities/id/7e8f230e-3f96-4efd-806d-72725b960303?source=cve
third-party-advisory
-
wordfence.com
/blog/2017/10/3-zero-day-plugin-vulnerabilities-exploited-wild/
press/media-coverage, third-party-advisory
Sources
- CVE List CVE-2017-20206
- NVD CVE-2017-20206
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