CVE-2026-18391 json
WooCommerce Subscriptions < 9.1.0 - Unauthenticated RCE via PHP Object Injection
published 2026-08-12 2 mo ago modified 2026-08-26 2 mo ago also EUVD-2026-57100
- cvss
- 9.8
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.0%
- EPSS 1.0% chance of exploitation in 30 days, percentile 61%
- public exploits
- 0
- none known
Summary
The WooCommerce Subscriptions WordPress plugin before 9.1.0 does not validate user input before unserializing it on stores with High-Performance Order Storage enabled, leading to a PHP Object Injection issue which unauthenticated users can escalate to Remote Code Execution via a gadget chain present in the bundled dependencies.
Patch / fix
- Unknown WooCommerce Subscriptions 9.1.0
CISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- yes
- Technical impact
- total
- Assessed
- 2 mo ago
Exploit prediction
0.96% chance of exploitation in the next 30 days, higher than 61% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- wpscan.com https://wpscan.com/vulnerability/191f76cf-e5bd-4a37-ac1c-9187cea2aa27/ referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CISA ADP | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| 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
- Unknown WooCommerce Subscriptions
Classification
- Weakness
-
- CWE-434 Unrestricted Upload of File with Dangerous Type
- Technology feeds
References
-
wpscan.com
/vulnerability/191f76cf-e5bd-4a37-ac1c-9187cea2aa27/
exploit, vdb-entry, technical-description
Sources
- CVE List CVE-2026-18391
- NVD CVE-2026-18391
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.