# CVE-2020-17437: Memory corruption in n/a

> A memory corruption vulnerability in Contiki OS allows attackers to cause denial of service or execute code via crafted TCP packets with large urgent pointers.

- **Severity:** High 8.2 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/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:** 11 Dec 2020
- **Updated:** 4 Aug 2024
- **Also known as:** DEBIAN-CVE-2020-17437, GHSA-cfgh-w4j7-hfhp, OESA-2022-1757, SUSE-SU-2022:2861-1, UBUNTU-CVE-2020-17437

## What is CVE-2020-17437?

CVE-2020-17437 is a high-severity memory corruption vulnerability in n/a, published on 11 Dec 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

An issue was discovered in uIP 1.0, as used in Contiki 3.0 and other products. When the Urgent flag is set in a TCP packet, and the stack is configured to ignore the urgent data, the stack attempts to use the value of the Urgent pointer bytes to separate the Urgent data from the normal data, by calculating the offset at which the normal data should be present in the global buffer. However, the length of this offset is not checked; therefore, for large values of the Urgent pointer bytes, the data pointer can point to memory that is way beyond the data buffer in uip_process in uip.c.

Weakness: CWE-787 (Out-of-bounds Write)

## Which versions are affected by CVE-2020-17437?

It affects 11 products.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `open-iscsi` | SUSE:Linux Enterprise Server 12 SP2-BCL | All versions | 2.0.873-46.17.2 |

Products: Open-Iscsi Project Open-Iscsi, Siemens Sentron 3va Com100 Firmware, Siemens Sentron 3va Com800 Firmware, Siemens Sentron 3va Dsp800 Firmware, Siemens Sentron Pac2200 Clp Firmware, Siemens Sentron Pac2200 Firmware, Siemens Sentron Pac3200 Firmware, Siemens Sentron Pac3200t Firmware, Siemens Sentron Pac3220 Firmware, Siemens Sentron Pac4200 Firmware, Uip Project Uip.

## How do I fix CVE-2020-17437?

Apply the vendor's patch.

## Is CVE-2020-17437 being exploited?

There is no known exploitation of CVE-2020-17437 in the wild and no public exploit code.

## Other vulnerabilities in n/a

- [CVE-2017-17840](https://insights.sbomify.com/CVE-2017-17840/): Memory corruption in n/a (high 7.8)
- [CVE-2020-13987](https://insights.sbomify.com/CVE-2020-13987/): Information disclosure in n/a (high 7.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-17437 and fix it if it is affected.

What it is: CVE-2020-17437 is a high-severity memory corruption vulnerability in n/a, published on 11 Dec 2020. 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-2020-17437 in the wild and no public exploit code.

Affected product: n/a. 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-2020-17437/ (Markdown: https://insights.sbomify.com/CVE-2020-17437/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-17437
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-17437
- OSV: https://osv.dev/vulnerability/CVE-2020-17437

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-17437/
Summaries are generated and may contain mistakes; the official description above is the record.