# CVE-2016-2563: Memory corruption in n/a

> A stack-based buffer overflow in PuTTY's SCP utility allows remote servers to execute arbitrary code or cause denial of service via crafted responses.

- **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:** Yes
- **Published:** 7 Apr 2016
- **Updated:** 5 Aug 2024
- **Also known as:** DEBIAN-CVE-2016-2563, GHSA-4hmm-v4j9-3hw2, MGASA-2016-0112, MGASA-2016-0118

## What is CVE-2016-2563?

CVE-2016-2563 is a critical memory corruption vulnerability in n/a, published on 7 Apr 2016. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Stack-based buffer overflow in the SCP command-line utility in PuTTY before 0.67 and KiTTY 0.66.6.3 and earlier allows remote servers to cause a denial of service (stack memory corruption) or execute arbitrary code via a crafted SCP-SINK file-size response to an SCP download request.

Weakness: CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer)

## Which versions are affected by CVE-2016-2563?

It affects 2 products.


Products: 9bis Kitty, Simon Tatham Putty.

## How do I fix CVE-2016-2563?

Upgrade to a fixed version.

## Is CVE-2016-2563 being exploited?

There is no known exploitation of CVE-2016-2563 in the wild and no public exploit code.

Public exploit code:

- Putty pscp 0.66 - Stack Buffer Overwrite (exploitdb)

## Other vulnerabilities in n/a

- [CVE-2024-23749](https://insights.sbomify.com/CVE-2024-23749/): Command injection in n/a (high 7.8)
- [CVE-2024-25003](https://insights.sbomify.com/CVE-2024-25003/): Memory corruption in n/a (high 7.8)
- [CVE-2024-25004](https://insights.sbomify.com/CVE-2024-25004/): Memory corruption in n/a (high 7.8)
- [CVE-2023-48795](https://insights.sbomify.com/CVE-2023-48795/): Prefix Truncation Attack against ChaCha20-Poly1305 and Encrypt-then-MAC aka Terrapin (medium 5.9)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2016-2563 and fix it if it is affected.

What it is: CVE-2016-2563 is a critical memory corruption vulnerability in n/a, published on 7 Apr 2016. 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-2016-2563 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-2016-2563/ (Markdown: https://insights.sbomify.com/CVE-2016-2563/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2016-2563
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2016-2563
- OSV: https://osv.dev/vulnerability/CVE-2016-2563

---
From sbomify Insights: https://insights.sbomify.com/CVE-2016-2563/
Summaries are generated and may contain mistakes; the official description above is the record.