# CVE-2018-14599: libx11-6: An issue was discovered in libX11 through 1.6.5

CVE-2018-14599 is fixed in 3 products on 1 platform, first by libx11-6 2:1.6.4-3ubuntu0.1, released August 23, 2018. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2018-14599
- Priority: Routine
- CVSS: n/a (Medium)
- EPSS: 0.0421
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Aug 23, 2018

## Description

An issue was discovered in libX11 through 1.6.5. The function XListExtensions in ListExt.c is vulnerable to an off-by-one error caused by malicious server responses, leading to DoS or possibly unspecified other impact.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | libx11-6 Ubuntu 18.04.6 LTS (bionic) | 2:1.6.4-3ubuntu0.1 | [libx11-6 2:1.6.4-3ubuntu0.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libx11-6-2-1.6.4-3ubuntu0.1.md) | Aug 23, 2018 |
| Linux | libx11-data Ubuntu 18.04.6 LTS (bionic) | 2:1.6.4-3ubuntu0.1 | [libx11-data 2:1.6.4-3ubuntu0.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libx11-data-2-1.6.4-3ubuntu0.1.md) | Aug 23, 2018 |
| Linux | libx11-xcb1 Ubuntu 18.04.6 LTS (bionic) | 2:1.6.4-3ubuntu0.1 | [libx11-xcb1 2:1.6.4-3ubuntu0.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libx11-xcb1-2-1.6.4-3ubuntu0.1.md) | Aug 23, 2018 |

---

Data as of 2026-11-07T12:40:37Z 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 Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo