# CVE-2018-0087: Auth bypass in Cisco Web Security Appliance

> Unauthenticated remote attackers can bypass FTP password validation on Cisco WSA if FTP is enabled, allowing unauthorized login with a valid username.

- **Severity:** Medium 5.6 (`CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 8 Mar 2018
- **Updated:** 2 Dec 2024
- **Also known as:** GHSA-9p96-pf4v-v529

## What is CVE-2018-0087?

CVE-2018-0087 is a medium-severity authentication bypass vulnerability in Cisco Asyncos, published on 8 Mar 2018. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A vulnerability in the FTP server of the Cisco Web Security Appliance (WSA) could allow an unauthenticated, remote attacker to log in to the FTP server of the device without a valid password. The attacker does need to have a valid username. The vulnerability is due to incorrect FTP user credential validation. An attacker could exploit this vulnerability by using FTP to connect to the management IP address of the targeted device. A successful exploit could allow the attacker to log in to the FTP server of the Cisco WSA without having a valid password. This vulnerability affects Cisco AsyncOS for WSA Software on both virtual and hardware appliances that are running any release of Cisco AsyncOS 10.5.1 for WSA Software. The device is vulnerable only if FTP is enabled on the management interface. FTP is disabled by default. Cisco Bug IDs: CSCvf74281.

Weakness: CWE-287 (Improper Authentication)

## Which versions are affected by CVE-2018-0087?

It affects 1 product.


Products: Cisco Asyncos.

## How do I fix CVE-2018-0087?

No fix has been published for CVE-2018-0087 yet. Limit exposure of the affected software until one is available.

## Is CVE-2018-0087 being exploited?

There is no known exploitation of CVE-2018-0087 in the wild and no public exploit code.

## Other vulnerabilities in Cisco Asyncos

- [CVE-2025-20393](https://insights.sbomify.com/CVE-2025-20393/): Cisco Multiple Products Improper Input Validation (critical 10.0, exploited in the wild)
- [CVE-2026-76519](https://insights.sbomify.com/CVE-2026-76519/): Cisco Secure Email Gateway Relative Path Traversal (critical 9.8, exploited in the wild)
- [CVE-2026-76461](https://insights.sbomify.com/CVE-2026-76461/): Cisco Secure Email Gateway SQL Injection (critical 9.8, exploited in the wild)
- [CVE-2024-20435](https://insights.sbomify.com/CVE-2024-20435/): Command injection in Cisco Secure Web Appliance (high 8.8)
- [CVE-2019-15956](https://insights.sbomify.com/CVE-2019-15956/): Cisco Web Security Appliance Unauthorized Device Reset Vulnerability (high 8.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2018-0087 and fix it if it is affected.

What it is: CVE-2018-0087 is a medium-severity authentication bypass vulnerability in Cisco Asyncos, published on 8 Mar 2018. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2018-0087 in the wild and no public exploit code.

Affected product: Cisco Asyncos. 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-2018-0087/ (Markdown: https://insights.sbomify.com/CVE-2018-0087/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2018-0087
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2018-0087
- OSV: https://osv.dev/vulnerability/CVE-2018-0087

---
From sbomify Insights: https://insights.sbomify.com/CVE-2018-0087/
Summaries are generated and may contain mistakes; the official description above is the record.