# CVE-2020-12884: Memory corruption in n/a

> A buffer over-read in the CoAP parser allows attackers to read out-of-bounds memory or cause a denial of service.

- **Severity:** Critical 9.1 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/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:** No
- **Published:** 18 Jun 2020
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-ghhj-m687-4jqx

## What is CVE-2020-12884?

CVE-2020-12884 is a critical memory corruption vulnerability in n/a, published on 18 Jun 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A buffer over-read was discovered in the CoAP library in Arm Mbed OS 5.15.3. The CoAP parser is responsible for parsing received CoAP packets. The function sn_coap_parser_options_parse_multiple_options() parses CoAP options that may occur multiple consecutive times in a single packet. While processing the options, packet_data_pptr is accessed after being incremented by option_len without a prior out-of-bounds memory check. The temp_parsed_uri_query_ptr is validated for a correct range, but the range valid for temp_parsed_uri_query_ptr is derived from the amount of allocated heap memory, not the actual input size. Therefore the check of temp_parsed_uri_query_ptr may be insufficient for safe access to the area pointed to by packet_data_pptr. As a result, access to a memory area outside of the intended boundary of the packet buffer is made.

Weakness: CWE-125 (Out-of-bounds Read)

## Which versions are affected by CVE-2020-12884?

It affects 1 product.


Products: Arm Mbed Os.

## How do I fix CVE-2020-12884?

No fix has been published for CVE-2020-12884 yet. Limit exposure of the affected software until one is available.

## Is CVE-2020-12884 being exploited?

There is no known exploitation of CVE-2020-12884 in the wild and no public exploit code.

## Other vulnerabilities in n/a

- [CVE-2024-48984](https://insights.sbomify.com/CVE-2024-48984/): Memory corruption in n/a (critical 9.8)
- [CVE-2020-12883](https://insights.sbomify.com/CVE-2020-12883/): Memory corruption in n/a (critical 9.1)
- [CVE-2020-12886](https://insights.sbomify.com/CVE-2020-12886/): Memory corruption in n/a (critical 9.1)
- [CVE-2020-12885](https://insights.sbomify.com/CVE-2020-12885/): Denial of service in n/a (high 7.5)
- [CVE-2024-22905](https://insights.sbomify.com/CVE-2024-22905/): Memory corruption in n/a (high 7.0)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-12884 and fix it if it is affected.

What it is: CVE-2020-12884 is a critical memory corruption vulnerability in n/a, published on 18 Jun 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-2020-12884 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-2020-12884/ (Markdown: https://insights.sbomify.com/CVE-2020-12884/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-12884
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-12884
- OSV: https://osv.dev/vulnerability/CVE-2020-12884

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-12884/
Summaries are generated and may contain mistakes; the official description above is the record.