Quick answers
- Is CVE-2026-72587 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-72587 being exploited in the wild.
- How severe is CVE-2026-72587?
- Medium severity, with a CVSS score of 6.1, published 10 August 2026.
- Which products and versions are affected?
- CoreBunch Instatic through 0.0.14.
- Is there a fix for CVE-2026-72587?
- No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
- How is CVE-2026-72587 attacked?
- It is attacked over the network, in a web application.
- Am I affected by CVE-2026-72587?
- Check whether you run CoreBunch Instatic at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
The vulnerability is a cache poisoning flaw in CoreBunch/Instatic versions through 0.0.14, accessible via the GET /_instatic/hole/<nodeId> server island endpoint. An unauthenticated remote attacker can manipulate the 'u' query parameter to inject malicious content into the process-wide render cache. This allows the attacker to poison cached responses that are served to all subsequent users without authentication or user interaction required. The attack targets the shared cache mechanism, causing legitimate users to receive attacker-controlled content from their normal requests.
Affected products
- CoreBunch Instatic through 0.0.14
Timeline
- 2026-08-10: disclosed