# CVE-2020-8905: Confidential Information Disclosure vulnerability in Asylo

> An attacker can read trusted memory data by exploiting a buffer length validation flaw in the Asylo library's network receive function.

- **Severity:** Low 2.8 (`CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:L/I:N/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 12 Aug 2020
- **Updated:** 17 Sep 2024
- **Also known as:** GHSA-xr5f-j5gc-qw6j

## What is CVE-2020-8905?

CVE-2020-8905 is a low-severity vulnerability in Google LLC Asylo, published on 12 Aug 2020. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

A buffer length validation vulnerability in Asylo versions prior to 0.6.0 allows an attacker to read data they should not have access to. The 'enc_untrusted_recvfrom' function generates a return value which is deserialized by 'MessageReader', and copied into three different 'extents'. The length of the third 'extents' is controlled by the outside world, and not verified on copy, allowing the attacker to force Asylo to copy trusted memory data into an untrusted buffer of significantly small length.. We recommend updating Asylo to version 0.6.0 or later.

Weakness: CWE-120 (Buffer Copy without Checking Size of Input)

## Which versions are affected by CVE-2020-8905?

It affects 1 product.


Products: Google Asylo.

## How do I fix CVE-2020-8905?

No fix has been published for CVE-2020-8905 yet. Limit exposure of the affected software until one is available.

## Is CVE-2020-8905 being exploited?

There is no known exploitation of CVE-2020-8905 in the wild and no public exploit code.

## Other vulnerabilities in Google LLC Asylo

- [CVE-2021-22548](https://insights.sbomify.com/CVE-2021-22548/): Arbitrary enclave memory overread vulnerability in Asylo TrustedPrimitives::UntrustedCall (medium 6.5)
- [CVE-2021-22549](https://insights.sbomify.com/CVE-2021-22549/): Arbitrary enclave memory overwrite vulnerability in Asylo TrustedPrimitives::UntrustedCall (medium 6.5)
- [CVE-2021-22550](https://insights.sbomify.com/CVE-2021-22550/): Enclave memory overwrite/overread vulnerability in Asylo UntrustedCacheMalloc::GetBuffer (medium 6.5)
- [CVE-2020-8904](https://insights.sbomify.com/CVE-2020-8904/): Arbitrary trusted memory overwrite vulnerability in Asylo (medium 6.4)
- [CVE-2021-22552](https://insights.sbomify.com/CVE-2021-22552/): Memory overread secure enclave in Asylo 0.6.2 (medium 5.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-8905 and fix it if it is affected.

What it is: CVE-2020-8905 is a low-severity vulnerability in Google LLC Asylo, published on 12 Aug 2020. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2020-8905 in the wild and no public exploit code.

Affected product: Google LLC Asylo. 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-2020-8905/ (Markdown: https://insights.sbomify.com/CVE-2020-8905/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-8905
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-8905
- OSV: https://osv.dev/vulnerability/CVE-2020-8905

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-8905/
Summaries are generated and may contain mistakes; the official description above is the record.