# CVE-2021-27135: xterm: The xterm program is a terminal emulator for the X Window System

CVE-2021-27135 is fixed in 2 products on 1 platform, first by xterm 330-1ubuntu2.2, released February 10, 2021. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2021-27135
- Priority: High
- CVSS: 9.8 (Important)
- EPSS: 0.0786
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Feb 10, 2021

## Description

The xterm program is a terminal emulator for the X Window System. It provides DEC VT102 and Tektronix 4014 compatible terminals for programs that can't use the window system directly.  Security Fix(es):  * xterm: crash when processing combining characters (CVE-2021-27135)  For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | xterm RHEL 8 | 0:331-1.el8_3.2 | [RHSA-2021:0611](https://patchblox.com/security/data/fix/linux/rhsa-2021-0611.md) | Feb 18, 2021 |
| Linux | xterm Ubuntu 18.04.6 LTS (bionic) | 330-1ubuntu2.2 | [xterm 330-1ubuntu2.2](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-xterm-330-1ubuntu2.2.md) | Feb 10, 2021 |
| Linux | xterm Ubuntu 20.04 LTS (focal) | 353-1ubuntu1.20.04.2 | [xterm 353-1ubuntu1.20.04.2](https://patchblox.com/security/data/fix/linux/ubuntu-focal-xterm-353-1ubuntu1.20.04.2.md) | Feb 10, 2021 |
| Linux | xterm ol 8 | 0:331-1.el8_3.2 | [ELSA-2021-0611](https://patchblox.com/security/data/fix/linux/elsa-2021-0611.md) | Feb 18, 2021 |
| Linux | xterm-resize RHEL 8 | 0:331-1.el8_3.2 | [RHSA-2021:0611](https://patchblox.com/security/data/fix/linux/rhsa-2021-0611.md) | Feb 18, 2021 |
| Linux | xterm-resize ol 8 | 0:331-1.el8_3.2 | [ELSA-2021-0611](https://patchblox.com/security/data/fix/linux/elsa-2021-0611.md) | Feb 18, 2021 |

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Data as of 2026-11-09T07:25:28Z 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 Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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