# CVE-2019-18805: Integer overflow in n/a

> A signed integer overflow in the Linux kernel TCP implementation allows local users to cause a denial of service by writing a large value to a specific proc file.

- **Severity:** Critical 9.8 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/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:** Not needed
- **Fix available:** Yes
- **Published:** 7 Nov 2019
- **Updated:** 5 Aug 2024
- **Also known as:** DEBIAN-CVE-2019-18805, GHSA-wgj3-wxrf-qqg3, UBUNTU-CVE-2019-18805

## What is CVE-2019-18805?

CVE-2019-18805 is a critical vulnerability in Broadcom Fabric Operating System, published on 7 Nov 2019. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

An issue was discovered in net/ipv4/sysctl_net_ipv4.c in the Linux kernel before 5.0.11. There is a net/ipv4/tcp_input.c signed integer overflow in tcp_ack_update_rtt() when userspace writes a very large integer to /proc/sys/net/ipv4/tcp_min_rtt_wlen, leading to a denial of service or possibly unspecified other impact, aka CID-19fad20d15a6.

Weakness: CWE-190 (Integer Overflow or Wraparound)

## Which versions are affected by CVE-2019-18805?

It affects 17 products.


Products: Broadcom Fabric Operating System, Linux kernel, Netapp Active Iq Unified Manager, Netapp Aff A400 Firmware, Netapp Aff A700s Firmware, Netapp Data Availability Services, Netapp E-Series Santricity Os Controller, Netapp Fas8300 Firmware, Netapp Fas8700 Firmware, Netapp H610s Firmware, Netapp Hci Compute Node, Netapp Hci Management Node, Netapp Hci Storage Node, Netapp Solidfire, Netapp Steelstore Cloud Integrated Storage, Opensuse Leap, Redhat Enterprise Linux.

## How do I fix CVE-2019-18805?

Upgrade to a fixed version.

## Is CVE-2019-18805 being exploited?

There is no known exploitation of CVE-2019-18805 in the wild and no public exploit code.

## Other vulnerabilities in Broadcom Fabric Operating System

- [CVE-2025-1976](https://insights.sbomify.com/CVE-2025-1976/): Broadcom Brocade Fabric OS Code Injection (high 8.6, exploited in the wild)
- [CVE-2021-22555](https://insights.sbomify.com/CVE-2021-22555/): Linux Kernel Heap Out-of-Bounds Write (high 8.3, exploited in the wild)
- [CVE-2022-33186](https://insights.sbomify.com/CVE-2022-33186/): Command injection in Brocade Fabric OS (critical 9.8)
- [CVE-2021-27797](https://insights.sbomify.com/CVE-2021-27797/): Hardcoded credentials in Brocade Fabric OS (critical 9.8)
- [CVE-2020-15371](https://insights.sbomify.com/CVE-2020-15371/): Code injection in Brocade Fabric OS (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2019-18805 and fix it if it is affected.

What it is: CVE-2019-18805 is a critical vulnerability in Broadcom Fabric Operating System, published on 7 Nov 2019. 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-2019-18805 in the wild and no public exploit code.

Affected product: Broadcom Fabric Operating System. 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-2019-18805/ (Markdown: https://insights.sbomify.com/CVE-2019-18805/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2019-18805
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2019-18805
- OSV: https://osv.dev/vulnerability/CVE-2019-18805

---
From sbomify Insights: https://insights.sbomify.com/CVE-2019-18805/
Summaries are generated and may contain mistakes; the official description above is the record.