# CVE-2026-115479: baserCMS: Mail-form auto-replies accept multiple visitor-controlled recipients


- **Severity:** Medium 5.3 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Fix available:** No
- **Published:** 23 Oct 2026
- **Updated:** 23 Oct 2026
- **Also known as:** GHSA-w47c-4g8m-gjv9

## What is CVE-2026-115479?

CVE-2026-115479 is a medium-severity vulnerability in baserproject basercms, published on 23 Oct 2026. 

### Official description

baserCMS is a website development framework. In versions 5.2.5 before 5.3.2 and 5.4.0 before 5.4.2, an unauthenticated visitor can supply a comma-separated address list in a public mail form's email field and cause a single auto-reply to be addressed to multiple third parties. MailMessageMailer::sendFormToUser() passes the visitor-controlled userMail value to parseAndNormalizeMailAddresses(), which splits it with explode(',') and supplies every resulting address to setTo(). Newly created forms with an email-type field are affected when the separate, optional VALID_EMAIL server-side validation is not enabled; browser type=email validation does not prevent crafted requests. The bundled contact form enables VALID_EMAIL and is not affected. The auto-reply uses the site's sender identity and includes partially attacker-controlled content, allowing abuse of the site to deliver unsolicited mail. This issue has been patched in versions 5.3.2 and 5.4.2.

Weakness: CWE-20 (Improper Input Validation)

## Which versions are affected by CVE-2026-115479?


## How do I fix CVE-2026-115479?

No fix has been published for CVE-2026-115479 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-115479 being exploited?

There is no known exploitation of CVE-2026-115479 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-115479 and fix it if it is affected.

What it is: CVE-2026-115479 is a medium-severity vulnerability in baserproject basercms, published on 23 Oct 2026. 
Exploitation: There is no known exploitation of CVE-2026-115479 in the wild and no public exploit code.

Affected product: baserproject basercms. 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-2026-115479/ (Markdown: https://insights.sbomify.com/CVE-2026-115479/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-115479
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-115479
- OSV: https://osv.dev/vulnerability/CVE-2026-115479

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-115479/
Summaries are generated and may contain mistakes; the official description above is the record.