# CVE-2016-3403: Cross-site request forgery in n/a

> Remote attackers can hijack administrator sessions to add, modify, or remove accounts in the Zimbra Admin Console due to missing CSRF protections.

- **Severity:** High 8.8 (`CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 17 May 2017
- **Updated:** 5 Aug 2024
- **Also known as:** CVE-2015-6542, GHSA-hvwj-rr9f-hc9j

## What is CVE-2016-3403?

CVE-2016-3403 is a high-severity vulnerability in Synacor Zimbra Collaboration Suite, published on 17 May 2017. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

### Official description

Multiple cross-site request forgery (CSRF) vulnerabilities in the Admin Console in Zimbra Collaboration before 8.6.0 Patch 8 allow remote attackers to hijack the authentication of administrators for requests that (1) add, (2) modify, or (3) remove accounts by leveraging failure to use of a CSRF token and perform referer header checks, aka bugs 100885 and 100899.

Weakness: CWE-352 (Cross-Site Request Forgery)

## Which versions are affected by CVE-2016-3403?

It affects 1 product.


Products: Synacor Zimbra Collaboration Suite.

## How do I fix CVE-2016-3403?

No fix has been published for CVE-2016-3403 yet. Limit exposure of the affected software until one is available.

## Is CVE-2016-3403 being exploited?

There is no known exploitation of CVE-2016-3403 in the wild and no public exploit code.

## Other vulnerabilities in Synacor Zimbra Collaboration Suite

- [CVE-2024-45519](https://insights.sbomify.com/CVE-2024-45519/): Synacor Zimbra Collaboration Suite (ZCS) Command Execution (critical 10.0, exploited in the wild)
- [CVE-2022-41352](https://insights.sbomify.com/CVE-2022-41352/): Synacor Zimbra Collaboration Suite (ZCS) Arbitrary File Upload (critical 9.8, exploited in the wild)
- [CVE-2022-37042](https://insights.sbomify.com/CVE-2022-37042/): Synacor Zimbra Collaboration Suite (ZCS) Authentication Bypass (critical 9.8, exploited in the wild)
- [CVE-2022-27924](https://insights.sbomify.com/CVE-2022-27924/): Synacor Zimbra Collaboration Suite (ZCS) Command Injection (critical 9.8, exploited in the wild)
- [CVE-2020-7796](https://insights.sbomify.com/CVE-2020-7796/): Synacor Zimbra Collaboration Suite (ZCS) Server-Side Request Forgery (critical 9.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2016-3403 and fix it if it is affected.

What it is: CVE-2016-3403 is a high-severity vulnerability in Synacor Zimbra Collaboration Suite, published on 17 May 2017. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2016-3403 in the wild and no public exploit code.

Affected product: Synacor Zimbra Collaboration Suite. 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-2016-3403/ (Markdown: https://insights.sbomify.com/CVE-2016-3403/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2016-3403
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2016-3403
- OSV: https://osv.dev/vulnerability/CVE-2016-3403

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From sbomify Insights: https://insights.sbomify.com/CVE-2016-3403/
Summaries are generated and may contain mistakes; the official description above is the record.