# CVE-2021-35942: Integer overflow in n/a

> An integer overflow in glibc's wordexp function allows attackers to cause crashes or read arbitrary memory via crafted patterns.

- **Severity:** Critical 9.1 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/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:** 22 Jul 2021
- **Updated:** 14 Oct 2026
- **Also known as:** CLSA-2026-1777456776, DEBIAN-CVE-2021-35942, GHSA-53wq-r63f-m33q, MGASA-2021-0362, OESA-2021-1296, UBUNTU-CVE-2021-35942

## What is CVE-2021-35942?

CVE-2021-35942 is a critical vulnerability in Debian Debian Linux, published on 22 Jul 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

The wordexp function in the GNU C Library (aka glibc) through 2.33 may crash or read arbitrary memory in parse_param (in posix/wordexp.c) when called with an untrusted, crafted pattern, potentially resulting in a denial of service or disclosure of information. This occurs because atoi was used but strtoul should have been used to ensure correct calculations.

Weakness: CWE-190 (Integer Overflow or Wraparound), CWE-704 (Incorrect Type Conversion or Cast)

## Which versions are affected by CVE-2021-35942?

It affects 7 products.


Products: Debian Debian Linux, Gnu Glibc, Netapp Active Iq Unified Manager, Netapp E-Series Santricity Os Controller, Netapp Hci Management Node, Netapp Ontap Select Deploy Administration Utility, Netapp Solidfire.

## How do I fix CVE-2021-35942?

Apply the vendor's patch.

## Is CVE-2021-35942 being exploited?

There is no known exploitation of CVE-2021-35942 in the wild and no public exploit code.

## Other vulnerabilities in Debian Debian Linux

- [CVE-2015-3306](https://insights.sbomify.com/CVE-2015-3306/): ProFTPD Improper Access Control (critical 10.0, exploited in the wild)
- [CVE-2025-49113](https://insights.sbomify.com/CVE-2025-49113/): RoundCube Webmail Deserialization of Untrusted Data (critical 9.9, exploited in the wild)
- [CVE-2026-24061](https://insights.sbomify.com/CVE-2026-24061/): GNU InetUtils Argument Injection (critical 9.8, exploited in the wild)
- [CVE-2025-39682](https://insights.sbomify.com/CVE-2025-39682/): Linux Kernel Improper Check for Unusual or Exceptional Conditions (critical 9.8, exploited in the wild)
- [CVE-2024-9680](https://insights.sbomify.com/CVE-2024-9680/): Mozilla Firefox Use-After-Free (critical 9.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-35942 and fix it if it is affected.

What it is: CVE-2021-35942 is a critical vulnerability in Debian Debian Linux, published on 22 Jul 2021. 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-2021-35942 in the wild and no public exploit code.

Affected product: Debian Debian Linux. 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-2021-35942/ (Markdown: https://insights.sbomify.com/CVE-2021-35942/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-35942
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-35942
- OSV: https://osv.dev/vulnerability/CVE-2021-35942

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-35942/
Summaries are generated and may contain mistakes; the official description above is the record.