Time Capsule Plugin vulnerability

WordPress Time Capsule Plugin 1.21.16 contains an authentication bypass vulnerability that allows unauthenticated attackers to gain administrative access by sending a crafted POST request with the IWP_JSON_PREFIX header. Attackers can exploit this flaw to obtain valid administrator session cookies and access the WordPress dashboard without providing credentials.

Published 20 Jun 2026Updated 29 Sep 20263 sources
CVSS 8.7

What happened

WordPress Time Capsule Plugin 1.21.16 contains an authentication bypass vulnerability that allows unauthenticated attackers to gain administrative access by sending a crafted POST request with the IWP_JSON_PREFIX header. Attackers can exploit this flaw to obtain valid administrator session cookies and access the WordPress dashboard without providing credentials.

Affected versions

Time Capsule Plugin: 0 through 1.21.16 (semver) Fixed: See vendor advisory.

Why it matters

Review the vendor advisory and exposure of the affected product to determine operational impact.

Detection & mitigation

  • Apply vendor-provided updates or mitigations.
  • Review affected product exposure and access logs.

Public PoC references

No public PoC reference has passed the current publication threshold.