Vulnerability in Appsmith (CVE-2026-49979)
Summary
Vulnerability in Appsmith (CVE-2026-49979). Risk of unauthorized operations or information disclosure. Exploitable via POST /api/v1/admin/send-test-email. Mitigation: upgrade to 1.99 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 1.99, the POST /api/v1/admin/send-test-email endpoint accepts attacker-controlled smtpHost and smtpPort values and establishes a raw JavaMail TCP connection without any IP validation. This completely bypasses WebClientUtils.IP_CHECK_FILTER, which only applies to Spring WebClient HTTP requests. Additionally, the raw MailException.getMessage() is returned verbatim in the API error response, enabling error-based internal port scanning and service banner enumeration. This vulnerability is fixed in 1.99.
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-2026-49979 has been found in Appsmith.
Attackers can target a specific entry point like POST /api/v1/admin/send-test-email over the network to misuse the product.
Risk of unauthorized operations or information disclosure. CVSS score: 2.7/10.
What to do: upgrade Appsmith to 1.99 or later.
If unsure, ask your IT team or search "Appsmith CVE-2026-49979" on the vendor's site.
CVE-2026-49979 (Appsmith) — CWE-209 / CVSS v3 2.7
Attack vector: remote (network-reachable) / no user interaction
Attack surface: POST /api/v1/admin/send-test-email
Patched: 1.99 — 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-209) exists in Appsmith. Attackers reach the vulnerable code path via POST /api/v1/admin/send-test-email.
Check the vendor advisory for the affected versions of Appsmith. Attack surface: POST /api/v1/admin/send-test-email.
Severity: Low (CVSS 2.7/10). Risk of unauthorized operations or information disclosure.
Update to 1.99.
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 /api/v1/admin/send-test-email 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 /api/v1/admin/send-test-email' /var/log/nginx/access.log | grep -E '(unusual_payload|sqli_pattern)'アクセスログで
POST /api/v1/admin/send-test-email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 1.99ステージング環境で 1.99 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 /api/v1/admin/send-test-email 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
- advisory nvd.nist.gov
- advisory github.com
- advisory github.com
- advisory kb.cert.org
- advisory github.com
- patch github.com
- web github.com
- web nvd.nist.gov