Vulnerability in Appsmith (CVE-2026-55454)
Summary
Vulnerability in Appsmith (CVE-2026-55454). Successful exploitation can lead to full system takeover. Exploitable via POST /load. Mitigation: upgrade to 2.1 or later.
Original description
The description as published by the source.
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.
Source: NIST National Vulnerability Database NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-55454 has been found in Appsmith.
Attackers can target a specific entry point like POST /load over the network to misuse the product.
Successful exploitation can lead to full system takeover. CVSS score: 9.9/10.
What to do: upgrade Appsmith to 2.1 or later.
If unsure, ask your IT team or search "Appsmith CVE-2026-55454" on the vendor's site.
CVE-2026-55454 (Appsmith) — CWE-749 / CVSS v3 9.9
Attack vector: remote (network-reachable) / no user interaction
Attack surface: POST /load
Patched: 2.1 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-749) exists in Appsmith. Attackers reach the vulnerable code path via POST /load.
Check the vendor advisory for the affected versions of Appsmith. Attack surface: POST /load.
Severity: Critical (CVSS 9.9/10). Successful exploitation can lead to full system takeover.
Update to 2.1.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual POST /load requests with malformed payloads or SQL meta-characters. Run grep -r 'Appsmith' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r 'Appsmith' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
Appsmithを grep し、稼働しているサービス・バージョンを把握する。 -
2Hunt for indicators of compromise detect
grep 'POST /load' /var/log/nginx/access.log | grep -E '(unusual_payload|sqli_pattern)'アクセスログで
POST /loadへの異常なリクエスト (不正な認証ヘッダ・SQLメタ文字)を過去 30〜90日分捜索。WAF/SIEM があれば該当パスのアラート発火履歴を確認。 -
3Apply patch patch
Upgrade Appsmith to 2.1ステージング環境で 2.1 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスと、Step 2 で見つけた異常検知の続報チェックを含めること。
-
4Post-deployment verification verify
Replay attack against POST /load on staging to confirm patch closes the vectorパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番では Step 2 と同じログクエリでアラート再発が無いか継続監視。
Affected packages
References
- advisory github.com
- web nvd.nist.gov