CVE-2026-18216 Backup Migration < 2.1.7 - Admin+ Privilege Escalation via Post-Restore Auto-Login
An administrator of one site in a WordPress multisite network can gain administrator access to another site via a flawed post-restore auto-login mechanism.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-18216?
CVE-2026-18216 is a medium-severity vulnerability in Unknown Backup Migration, published on 15 Aug 2026. An attacker needs administrator access to exploit it, with no action from the victim.
Official description
The Backup Migration WordPress plugin before 2.1.7 does not properly restrict a post-restore automatic login mechanism, allowing a user who administers one site of a multisite network to obtain a long-lived authenticated session as an administrator of another site in the same network, without credentials and bypassing two-factor authentication.
Weakness: CWE-287
Which versions are affected by CVE-2026-18216?
How do I fix CVE-2026-18216?
No fix has been published for CVE-2026-18216 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-18216 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-18216 exists.
Sources
Also known as GHSA-g4x6-qr8w-c3x7.