Appsmith is a platform to build admin panels, internal tools, and dashboards. Prior to 2.1, the bundled Caddy reverse-proxy's admin API — which has no authentication by default — is bound on 0.0.0.0:2019 inside the container. While this listener is not directly published to the host by docker-compose.yml, it is reachable from the Appsmith server process itself or a SSRF vulnerability. An authenticated low-privileged user can therefore drive the SSRF to issue POST /load (or any other admin-API call) against http://0.0.0.0:2019/, fully replacing the live Caddy configuration and taking over the reverse proxy. This vulnerability is fixed in 2.1.
Exploitability
AV:NAC:LPR:LUI:NScope
S:CImpact
C:HI:HA:H9.9/CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H