# CVE-2021-31535: libX11-common: The libX11 packages contain the core X11 protocol client library.  Security Fix(es):  * libX11: missing request lengt...

CVE-2021-31535 is fixed in 7 products on 1 platform, first by libx11-6 2:1.6.4-3ubuntu0.4, released May 17, 2021. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2021-31535
- Priority: High
- CVSS: 9.8 (Moderate)
- EPSS: 0.1035
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: May 17, 2021

## Description

The libX11 packages contain the core X11 protocol client library.  Security Fix(es):  * libX11: missing request length checks (CVE-2021-31535)  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.  Additional Changes:  For detailed information on changes in this release, see the Red Hat Enterprise Linux 8.5 Release Notes linked from the References section.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | libX11 RHEL 8 | 0:1.6.8-5.el8 | [RHSA-2021:4326](https://patchblox.com/security/data/fix/linux/rhsa-2021-4326.md) | Nov 9, 2021 |
| Linux | libX11 ol 8 | 0:1.6.8-5.el8 | [ELSA-2021-4326](https://patchblox.com/security/data/fix/linux/elsa-2021-4326.md) | Nov 16, 2021 |
| Linux | libX11-common RHEL 8 | 0:1.6.8-5.el8 | [RHSA-2021:4326](https://patchblox.com/security/data/fix/linux/rhsa-2021-4326.md) | Nov 9, 2021 |
| Linux | libX11-common ol 8 | 0:1.6.8-5.el8 | [ELSA-2021-4326](https://patchblox.com/security/data/fix/linux/elsa-2021-4326.md) | Nov 16, 2021 |
| Linux | libX11-devel RHEL 8 | 0:1.6.8-5.el8 | [RHSA-2021:4326](https://patchblox.com/security/data/fix/linux/rhsa-2021-4326.md) | Nov 9, 2021 |
| Linux | libX11-devel ol 8 | 0:1.6.8-5.el8 | [ELSA-2021-4326](https://patchblox.com/security/data/fix/linux/elsa-2021-4326.md) | Nov 16, 2021 |
| Linux | libX11-xcb RHEL 8 | 0:1.6.8-5.el8 | [RHSA-2021:4326](https://patchblox.com/security/data/fix/linux/rhsa-2021-4326.md) | Nov 9, 2021 |
| Linux | libX11-xcb ol 8 | 0:1.6.8-5.el8 | [ELSA-2021-4326](https://patchblox.com/security/data/fix/linux/elsa-2021-4326.md) | Nov 16, 2021 |
| Linux | libx11-6 Ubuntu 18.04.6 LTS (bionic) | 2:1.6.4-3ubuntu0.4 | [libx11-6 2:1.6.4-3ubuntu0.4](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libx11-6-2-1.6.4-3ubuntu0.4.md) | May 17, 2021 |
| Linux | libx11-6 Ubuntu 20.04 LTS (focal) | 2:1.6.9-2ubuntu1.2 | [libx11-6 2:1.6.9-2ubuntu1.2](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libx11-6-2-1.6.9-2ubuntu1.2.md) | May 17, 2021 |
| Linux | libx11-data Ubuntu 18.04.6 LTS (bionic) | 2:1.6.4-3ubuntu0.4 | [libx11-data 2:1.6.4-3ubuntu0.4](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libx11-data-2-1.6.4-3ubuntu0.4.md) | May 17, 2021 |
| Linux | libx11-data Ubuntu 20.04 LTS (focal) | 2:1.6.9-2ubuntu1.2 | [libx11-data 2:1.6.9-2ubuntu1.2](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libx11-data-2-1.6.9-2ubuntu1.2.md) | May 17, 2021 |
| Linux | libx11-xcb1 Ubuntu 18.04.6 LTS (bionic) | 2:1.6.4-3ubuntu0.4 | [libx11-xcb1 2:1.6.4-3ubuntu0.4](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libx11-xcb1-2-1.6.4-3ubuntu0.4.md) | May 17, 2021 |
| Linux | libx11-xcb1 Ubuntu 20.04 LTS (focal) | 2:1.6.9-2ubuntu1.2 | [libx11-xcb1 2:1.6.9-2ubuntu1.2](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libx11-xcb1-2-1.6.9-2ubuntu1.2.md) | May 17, 2021 |

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