# CVE-2016-9401: bash-static: popd in bash might allow local users to bypass the restricted shell and cause a use-after-free via a crafted address.

CVE-2016-9401 is fixed in 3 products on 1 platform, first by bash 4.4-5ubuntu1, released January 22, 2017. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2016-9401
- Priority: Routine
- CVSS: n/a (Negligible)
- EPSS: 0.0042
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Jan 22, 2017

## Description

popd in bash might allow local users to bypass the restricted shell and cause a use-after-free via a crafted address.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | bash Ubuntu 18.04.6 LTS (bionic) | 4.4-5ubuntu1 | [bash 4.4-5ubuntu1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-bash-4.4-5ubuntu1.md) | Jan 22, 2017 |
| Linux | bash-builtins Ubuntu 18.04.6 LTS (bionic) | 4.4-5ubuntu1 | [bash-builtins 4.4-5ubuntu1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-bash-builtins-4.4-5ubuntu1.md) | Jan 22, 2017 |
| Linux | bash-static Ubuntu 18.04.6 LTS (bionic) | 4.4-5ubuntu1 | [bash-static 4.4-5ubuntu1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-bash-static-4.4-5ubuntu1.md) | Jan 22, 2017 |

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Data as of 2026-11-07T06:34:28Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo