# CVE-2019-18634: sudo: In Sudo before 1.8.26, if pwfeedback is enabled in /etc/sudoers, users can trigger a stack-based buffer overflow in t...

CVE-2019-18634 is fixed in 2 products on 1 platform, first by sudo 1.8.21p2-3ubuntu1.2, released January 30, 2020. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2019-18634
- Priority: High
- CVSS: 7.8 (Low)
- EPSS: 0.1928
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Jan 30, 2020

## Description

In Sudo before 1.8.26, if pwfeedback is enabled in /etc/sudoers, users can trigger a stack-based buffer overflow in the privileged sudo process. (pwfeedback is a default setting in Linux Mint and elementary OS; however, it is NOT the default for upstream and many other packages, and would exist only if enabled by an administrator.) The attacker needs to deliver a long string to the stdin of getln() in tgetpass.c.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | sudo RHEL 8 | 0:1.8.25p1-8.el8_1.1 | [RHSA-2020:0487](https://patchblox.com/security/data/fix/linux/rhsa-2020-0487.md) | Feb 14, 2020 |
| Linux | sudo Ubuntu 18.04.6 LTS (bionic) | 1.8.21p2-3ubuntu1.2 | [sudo 1.8.21p2-3ubuntu1.2](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-sudo-1.8.21p2-3ubuntu1.2.md) | Jan 30, 2020 |
| Linux | sudo ol 8 | 0:1.8.25p1-8.el8_1.1 | [ELSA-2020-0487](https://patchblox.com/security/data/fix/linux/elsa-2020-0487.md) | Feb 13, 2020 |
| Linux | sudo-ldap Ubuntu 18.04.6 LTS (bionic) | 1.8.21p2-3ubuntu1.2 | [sudo-ldap 1.8.21p2-3ubuntu1.2](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-sudo-ldap-1.8.21p2-3ubuntu1.2.md) | Jan 30, 2020 |

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