CVE-2026-55455
Appsmith is a platform to build admin panels, internal tools, and dashboards. Prior to 2.1, the outbound HTTP host filter applied by WebClientUtils (used by the REST API and GraphQL datasource plugins) validates hosts against an exact-match string denylist. The comprehensive address-class check (loopback, any-local, link-local, fc00::/7) exists only on a separate code path used by SMTP, not by the HTTP plugin path. As a result, an authenticated user can craft outbound requests that reach loopback-bound services inside the container. This vulnerability is fixed in 2.1.
- Affected products
- Appsmith
- Appsmith
- < 2.1
- Fix
- Available
- CVSS 3.1
- 9.1 CRITICAL
- EPSS
- 0.2% (13th percentile)
- Weakness
- CWE-918
- NVD status
- Analyzed
- Published
- 2026-06-24
No indexed exploits for CVE-2026-55455 yet
Our index is partial: it proves presence, never absence
No exploit for CVE-2026-55455 has been indexed yet. Our index is built from live traffic and upstream syncs, so this page can only say what it knows — not that no exploit exists.