# CVE-2011-5320: Denial of service in n/a

> Local attackers can cause a segmentation fault and denial of service in applications using glibc scanf functions by providing a large string of zeros.

- **Severity:** Medium 6.2 (`CVSS:3.0/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 18 Oct 2017
- **Updated:** 7 Aug 2024
- **Also known as:** DEBIAN-CVE-2011-5320, GHSA-m3xm-963r-gm9q

## What is CVE-2011-5320?

CVE-2011-5320 is a medium-severity denial of service vulnerability in Gnu Glibc, published on 18 Oct 2017. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

scanf and related functions in glibc before 2.15 allow local users to cause a denial of service (segmentation fault) via a large string of 0s.

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

## Which versions are affected by CVE-2011-5320?

It affects 1 product.


Products: Gnu Glibc.

## How do I fix CVE-2011-5320?

Upgrade to a fixed version.

## Is CVE-2011-5320 being exploited?

There is no known exploitation of CVE-2011-5320 in the wild and no public exploit code.

## Other vulnerabilities in Gnu Glibc

- [CVE-2026-5450](https://insights.sbomify.com/CVE-2026-5450/): scanf %mc off-by-one heap buffer overflow (critical 9.8)
- [CVE-2023-25139](https://insights.sbomify.com/CVE-2023-25139/): Memory corruption in n/a (critical 9.8)
- [CVE-1999-0199](https://insights.sbomify.com/CVE-1999-0199/): Other in n/a (critical 9.8)
- [CVE-2019-1010022](https://insights.sbomify.com/CVE-2019-1010022/): Security feature bypass in glibc (critical 9.8)
- [CVE-2005-3590](https://insights.sbomify.com/CVE-2005-3590/): Memory corruption in n/a (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2011-5320 and fix it if it is affected.

What it is: CVE-2011-5320 is a medium-severity denial of service vulnerability in Gnu Glibc, published on 18 Oct 2017. 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-2011-5320 in the wild and no public exploit code.

Affected product: Gnu Glibc. 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-2011-5320/ (Markdown: https://insights.sbomify.com/CVE-2011-5320/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2011-5320
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2011-5320
- OSV: https://osv.dev/vulnerability/CVE-2011-5320

---
From sbomify Insights: https://insights.sbomify.com/CVE-2011-5320/
Summaries are generated and may contain mistakes; the official description above is the record.