# CVE-2019-15680: libvncclient1: TightVNC code version 1.3.10 contains null pointer dereference in HandleZlibBPP function, which results Denial of Sys...

CVE-2019-15680 is fixed in 3 products on 1 platform, first by libvncclient1 0.9.11+dfsg-1ubuntu1.2, released June 30, 2020. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2019-15680
- Priority: Routine
- CVSS: n/a (Low)
- EPSS: 0.0267
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Oct 29, 2019

## Description

TightVNC code version 1.3.10 contains null pointer dereference in HandleZlibBPP function, which results Denial of System (DoS). This attack appear to be exploitable via network connectivity.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | libvncclient1 Ubuntu 18.04.6 LTS (bionic) | 0.9.11+dfsg-1ubuntu1.2 | [libvncclient1 0.9.11+dfsg-1ubuntu1.2](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libvncclient1-0.9.11-dfsg-1ubuntu1.2.md) | Jun 30, 2020 |
| Linux | libvncclient1 Ubuntu 20.04 LTS (focal) | 0.9.12+dfsg-9ubuntu0.1 | [libvncclient1 0.9.12+dfsg-9ubuntu0.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libvncclient1-0.9.12-dfsg-9ubuntu0.1.md) | Jun 30, 2020 |
| Linux | libvncserver-config Ubuntu 18.04.6 LTS (bionic) | 0.9.11+dfsg-1ubuntu1.2 | [libvncserver-config 0.9.11+dfsg-1ubuntu1.2](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libvncserver-config-0.9.11-dfsg-1ubuntu1.2.md) | Jun 30, 2020 |
| Linux | libvncserver1 Ubuntu 18.04.6 LTS (bionic) | 0.9.11+dfsg-1ubuntu1.2 | [libvncserver1 0.9.11+dfsg-1ubuntu1.2](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libvncserver1-0.9.11-dfsg-1ubuntu1.2.md) | Jun 30, 2020 |
| Linux | libvncserver1 Ubuntu 20.04 LTS (focal) | 0.9.12+dfsg-9ubuntu0.1 | [libvncserver1 0.9.12+dfsg-9ubuntu0.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libvncserver1-0.9.12-dfsg-9ubuntu0.1.md) | Jun 30, 2020 |

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Data as of 2026-11-08T00:53:09Z 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 Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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