# CVE-2017-8307: Missing authorization in n/a

> Unprivileged users can launch binaries or modify files via the Avast service API when Self-Defense is disabled, enabling DoS or evidence tampering.

- **Severity:** Critical 9.8 (`CVSS:3.0/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:** 27 Apr 2017
- **Updated:** 5 Aug 2024
- **Also known as:** GHSA-7gqh-6434-f3jx

## What is CVE-2017-8307?

CVE-2017-8307 is a critical missing authorization vulnerability in n/a, published on 27 Apr 2017. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

In Avast Antivirus before v17, using the LPC interface API exposed by the AvastSVC.exe Windows service, it is possible to launch predefined binaries, or replace or delete arbitrary files. This vulnerability is exploitable by any unprivileged user when Avast Self-Defense is disabled. It is also exploitable in conjunction with CVE-2017-8308 when Avast Self-Defense is enabled. The vulnerability allows for Denial of Service attacks and hiding traces of a possible attack.

## Which versions are affected by CVE-2017-8307?

It affects 1 product.


Products: Avast Antivirus.

## How do I fix CVE-2017-8307?

No fix has been published for CVE-2017-8307 yet. Limit exposure of the affected software until one is available.

## Is CVE-2017-8307 being exploited?

There is no known exploitation of CVE-2017-8307 in the wild and no public exploit code.

## Other vulnerabilities in n/a

- [CVE-2025-13032](https://insights.sbomify.com/CVE-2025-13032/): Race condition in (Free/Inernet Security/Ultimate) Antivirus (critical 9.9)
- [CVE-2020-10867](https://insights.sbomify.com/CVE-2020-10867/): Security feature bypass in n/a (critical 9.8)
- [CVE-2025-3500](https://insights.sbomify.com/CVE-2025-3500/): Integer Overflow in Avast Antiviurs 25.1.981.6 on Windows may result in privilege escalation (critical 9.0)
- [CVE-2021-45335](https://insights.sbomify.com/CVE-2021-45335/): Missing authorization in n/a (high 8.8)
- [CVE-2021-45336](https://insights.sbomify.com/CVE-2021-45336/): Privilege escalation vulnerability in the Sandbox component of Avast Antivirus prior to 20.4 allows a local sandboxed code to gain elevated (high 8.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2017-8307 and fix it if it is affected.

What it is: CVE-2017-8307 is a critical missing authorization vulnerability in n/a, published on 27 Apr 2017. 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-2017-8307 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-2017-8307/ (Markdown: https://insights.sbomify.com/CVE-2017-8307/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2017-8307
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2017-8307
- OSV: https://osv.dev/vulnerability/CVE-2017-8307

---
From sbomify Insights: https://insights.sbomify.com/CVE-2017-8307/
Summaries are generated and may contain mistakes; the official description above is the record.