# CVE-2020-14936: Memory corruption in n/a

> Remote attackers can execute arbitrary code on IoT devices by sending crafted SNMP requests that trigger buffer overflows in the Contiki-NG SNMP agent.

- **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:** No
- **Published:** 18 Aug 2020
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-jrf8-p6cc-fr4f

## What is CVE-2020-14936?

CVE-2020-14936 is a critical memory corruption vulnerability in n/a, published on 18 Aug 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Buffer overflows were discovered in Contiki-NG 4.4 through 4.5, in the SNMP agent. Functions parsing the OIDs in SNMP requests lack sufficient allocated target-buffer capacity verification when writing parsed OID values. The function snmp_oid_decode_oid() may overwrite memory areas beyond the provided target buffer, when called from snmp_message_decode() upon an SNMP request reception. Because the content of the write operations is externally provided in the SNMP requests, it enables a remote overwrite of an IoT device's memory regions beyond the allocated buffer. This overflow may allow remote overwrite of stack and statically allocated variables memory regions by sending a crafted SNMP request.

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

## Which versions are affected by CVE-2020-14936?

It affects 1 product.


Products: Contiki-Ng Contiki-Ng.

## How do I fix CVE-2020-14936?

No fix has been published for CVE-2020-14936 yet. Limit exposure of the affected software until one is available.

## Is CVE-2020-14936 being exploited?

There is no known exploitation of CVE-2020-14936 in the wild and no public exploit code.

## Other vulnerabilities in n/a

- [CVE-2018-19417](https://insights.sbomify.com/CVE-2018-19417/): Memory corruption in n/a (critical 10.0)
- [CVE-2023-30546](https://insights.sbomify.com/CVE-2023-30546/): Contiki-NG has off-by-one error in Antelope DBMS (critical 9.8)
- [CVE-2020-24336](https://insights.sbomify.com/CVE-2020-24336/): Memory corruption in n/a (critical 9.8)
- [CVE-2020-14934](https://insights.sbomify.com/CVE-2020-14934/): Memory corruption in n/a (critical 9.8)
- [CVE-2020-14935](https://insights.sbomify.com/CVE-2020-14935/): Memory corruption in n/a (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-14936 and fix it if it is affected.

What it is: CVE-2020-14936 is a critical memory corruption vulnerability in n/a, published on 18 Aug 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-2020-14936 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-2020-14936/ (Markdown: https://insights.sbomify.com/CVE-2020-14936/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-14936
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-14936
- OSV: https://osv.dev/vulnerability/CVE-2020-14936

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-14936/
Summaries are generated and may contain mistakes; the official description above is the record.