# CVE-2026-49979: Appsmith: SSRF via `POST /api/v1/admin/send-test-email` — JavaMail Bypasses WebClient IP Filter

> Attackers can exploit an SSRF vulnerability in Appsmith's email testing endpoint to bypass IP filters and enumerate internal services via error messages.

- **Severity:** Medium 5.1 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:L/VI:N/VA:N/SC:L/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 24 Jun 2026
- **Updated:** 26 Jun 2026

## What is CVE-2026-49979?

CVE-2026-49979 is a medium-severity server-side request forgery vulnerability in appsmithorg appsmith, published on 24 Jun 2026. An attacker needs administrator access to exploit it, with no action from the victim.

### Official description

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.

Weakness: CWE-918 (Server-Side Request Forgery), CWE-209 (Generation of Error Message Containing Sensitive Information)

## Which versions are affected by CVE-2026-49979?

It affects 1 product.


Products: Appsmith Appsmith.

## How do I fix CVE-2026-49979?

Upgrade to a fixed version.

## Is CVE-2026-49979 being exploited?

There is no known exploitation of CVE-2026-49979 in the wild and no public exploit code.

## Other vulnerabilities in appsmithorg appsmith

- [CVE-2026-55454](https://insights.sbomify.com/CVE-2026-55454/): Appsmith: Caddy admin API exposed without authentication (critical 9.9)
- [CVE-2024-55964](https://insights.sbomify.com/CVE-2024-55964/): Code injection in n/a (critical 9.8)
- [CVE-2026-22794](https://insights.sbomify.com/CVE-2026-22794/): Account Takeover Vulnerability in Appsmith (critical 9.7)
- [CVE-2026-24042](https://insights.sbomify.com/CVE-2026-24042/): Appsmith public apps can execute unpublished actions (viewMode confusion) (critical 9.4)
- [CVE-2026-30862](https://insights.sbomify.com/CVE-2026-30862/): Critical Stored XSS & Privilege Escalation in Appsmith (critical 9.1)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-49979 and fix it if it is affected.

What it is: CVE-2026-49979 is a medium-severity server-side request forgery vulnerability in appsmithorg appsmith, published on 24 Jun 2026. An attacker needs administrator access to exploit it, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-49979 in the wild and no public exploit code.

Affected product: appsmithorg appsmith. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-49979/ (Markdown: https://insights.sbomify.com/CVE-2026-49979/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-49979
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-49979
- OSV: https://osv.dev/vulnerability/CVE-2026-49979

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-49979/
Summaries are generated and may contain mistakes; the official description above is the record.