# CVE-1999-0116: Denial of service in n/a

> Attackers can cause denial of service by flooding the system with SYN packets, affecting Unix-based operating systems.

- **Severity:** Medium 5.0 (`AV:N/AC:L/Au:N/C:N/I:N/A:P`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 29 Sep 1999
- **Updated:** 1 Aug 2024
- **Also known as:** GHSA-j56q-jrrm-mwmf

## What is CVE-1999-0116?

CVE-1999-0116 is a medium-severity denial of service vulnerability in Ibm Aix, published on 29 Sep 1999. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Denial of service when an attacker sends many SYN packets to create multiple connections without ever sending an ACK to complete the connection, aka SYN flood.

## Which versions are affected by CVE-1999-0116?

It affects 2 products.


Products: Ibm Aix, Ibm Sng.

## How do I fix CVE-1999-0116?

No fix has been published for CVE-1999-0116 yet. Limit exposure of the affected software until one is available.

## Is CVE-1999-0116 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-1999-0116 exists.

Public exploit code:

- TCP SYN - 'bang.c' Denial of Service (exploitdb)

## Other vulnerabilities in Ibm Aix

- [CVE-2025-36250](https://insights.sbomify.com/CVE-2025-36250/): AIX Code Execution (critical 10.0)
- [CVE-2024-56346](https://insights.sbomify.com/CVE-2024-56346/): IBM AIX command execution (critical 10.0)
- [CVE-2010-3187](https://insights.sbomify.com/CVE-2010-3187/): Memory corruption in n/a (critical 10.0)
- [CVE-2009-3699](https://insights.sbomify.com/CVE-2009-3699/): Memory corruption in n/a (critical 10.0)
- [CVE-2009-3517](https://insights.sbomify.com/CVE-2009-3517/): Auth bypass in n/a (critical 10.0)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-1999-0116 and fix it if it is affected.

What it is: CVE-1999-0116 is a medium-severity denial of service vulnerability in Ibm Aix, published on 29 Sep 1999. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-1999-0116 exists.

Affected product: Ibm Aix. 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-1999-0116/ (Markdown: https://insights.sbomify.com/CVE-1999-0116/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-1999-0116
- NVD: https://nvd.nist.gov/vuln/detail/CVE-1999-0116
- OSV: https://osv.dev/vulnerability/CVE-1999-0116

---
From sbomify Insights: https://insights.sbomify.com/CVE-1999-0116/
Summaries are generated and may contain mistakes; the official description above is the record.