Quick answers
- Is CVE-2026-36615 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-36615 being exploited in the wild.
- How severe is CVE-2026-36615?
- Informational severity, with a CVSS score of 4.3, published 3 June 2026.
- Which products and versions are affected?
- Mercusys AC12G AC12G(EU)_V1_200909, AC12G(EU)_V1_210128.
- Is there a fix for CVE-2026-36615?
- 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-2026-36615 attacked?
- It is attacked from the adjacent network, in a network appliance.
- Am I affected by CVE-2026-36615?
- Check whether you run Mercusys AC12G 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 HTTP handler for the undocumented /agileconfigreset endpoint fails to properly manage internal buffers, leading to an information disclosure vulnerability. When an unauthenticated attacker sends a POST request to this endpoint, the router returns a malformed response containing 128 bytes of the internal HTTP header parse buffer. This buffer contains null-separated header names and values from the current request and potentially data from other clients' requests due to a shared buffer pool. The vulnerability is confirmed in firmware versions AC12G(EU)_V1_200909 and AC12G(EU)_V1_210128.
Affected products
- Mercusys AC12G (EU) V1 AC12G(EU)_V1_200909, AC12G(EU)_V1_210128
Timeline
- 2026-06-03: disclosed
- 2026-06-03: advisory