# CVE-2017-1000099: Information disclosure in n/a

> An attacker can read uninitialized heap memory via file:// URL requests in libcurl, potentially exposing sensitive private data.

- **Severity:** Medium 6.5 (`CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** Yes
- **Published:** 4 Oct 2017
- **Updated:** 5 Aug 2024
- **Also known as:** ALPINE-CVE-2017-1000099, CLEANSTART-2026-DV20769, CURL-CVE-2017-1000099, GHSA-q937-ph5c-26qf

## What is CVE-2017-1000099?

CVE-2017-1000099 is a medium-severity vulnerability in Haxx Libcurl, published on 4 Oct 2017. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

### Official description

When asking to get a file from a file:// URL, libcurl provides a feature that outputs meta-data about the file using HTTP-like headers. The code doing this would send the wrong buffer to the user (stdout or the application's provide callback), which could lead to other private data from the heap to get inadvertently displayed. The wrong buffer was an uninitialized memory area allocated on the heap and if it turned out to not contain any zero byte, it would continue and display the data following that buffer in memory.

Weakness: CWE-200 (Exposure of Sensitive Information to an Unauthorized Actor)

## Which versions are affected by CVE-2017-1000099?

It affects 1 product.


Products: Haxx Libcurl.

## How do I fix CVE-2017-1000099?

Upgrade to a fixed version.

## Is CVE-2017-1000099 being exploited?

There is no known exploitation of CVE-2017-1000099 in the wild and no public exploit code.

## Other vulnerabilities in Haxx Libcurl

- [CVE-2024-6197](https://insights.sbomify.com/CVE-2024-6197/): freeing stack buffer in utf8asn1str (high 7.5)
- [CVE-2017-1000254](https://insights.sbomify.com/CVE-2017-1000254/): Memory corruption in n/a (high 7.5)
- [CVE-2016-7141](https://insights.sbomify.com/CVE-2016-7141/): Auth bypass in n/a (high 7.5)
- [CVE-2017-1000100](https://insights.sbomify.com/CVE-2017-1000100/): Information disclosure in n/a (medium 6.5)
- [CVE-2024-7264](https://insights.sbomify.com/CVE-2024-7264/): ASN.1 date parser overread (medium 6.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2017-1000099 and fix it if it is affected.

What it is: CVE-2017-1000099 is a medium-severity vulnerability in Haxx Libcurl, published on 4 Oct 2017. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2017-1000099 in the wild and no public exploit code.

Affected product: Haxx Libcurl. 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-2017-1000099/ (Markdown: https://insights.sbomify.com/CVE-2017-1000099/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2017-1000099
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2017-1000099
- OSV: https://osv.dev/vulnerability/CVE-2017-1000099

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From sbomify Insights: https://insights.sbomify.com/CVE-2017-1000099/
Summaries are generated and may contain mistakes; the official description above is the record.