Description
A divide by zero issue was found to occur in libvncserver-0.9.12. A malicious client could use this flaw to send a specially crafted message that, when processed by the VNC server, would lead to a floating point exception, resulting in a denial of service.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| — | libvncserver | libvncserver 0.9.12 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | libvncserver | 0.9.13+dfsg-1 | — |
| Debian 13 | libvncserver | 0.9.13+dfsg-1 | — |
| Debian 12 | libvncserver | 0.9.13+dfsg-1 | — |
| Debian 10 | libvncserver | 0.9.11+dfsg-1.3+deb10u5 | DLA-3125-1 |
| Debian 9 | libvncserver | 0.9.11+dfsg-1.3~deb9u6 | DLA-2451-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | veyon +1 | No fix yet | — |
| Ubuntu 26.04 LTS | veyon +1 | No fix yet | — |
| Ubuntu 25.10 | veyon +1 | No fix yet | — |
| Ubuntu 24.04 LTS | veyon +1 | No fix yet | — |
| Ubuntu 24.04 LTS | vino | 3.22.0-6ubuntu3 | — |
| Ubuntu 22.04 LTS | veyon +1 | No fix yet | — |
| Ubuntu 22.04 LTS | vino | 3.22.0-6ubuntu3 | — |
Show 5 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 20.04 LTS | libvncserver | 0.9.12+dfsg-9ubuntu0.3 | USN-4636-1 |
| Ubuntu 20.04 LTS | veyon +1 | No fix yet | — |
| Ubuntu 20.04 LTS | vino | 3.22.0-5ubuntu2.2 | USN-4636-1 |
| Ubuntu 18.04 LTS | italc +1 | No fix yet | — |
| Ubuntu 18.04 LTS | libvncserver | 0.9.11+dfsg-1ubuntu1.4 | USN-4636-1 |
| Ubuntu 18.04 LTS | vino | 3.22.0-3ubuntu1.2 | USN-4636-1 |
| Ubuntu 16.04 LTS | italc +1 | No fix yet | — |
| Ubuntu 16.04 LTS | libvncserver | 0.9.10+dfsg-3ubuntu0.16.04.6 | USN-4636-1 |
| Ubuntu 16.04 LTS | vino | 3.8.1-0ubuntu9.4 | USN-4636-1 |
| Ubuntu 14.04 LTS | x11vnc | No fix yet | — |
| Ubuntu Pro 14.04 LTS | tightvnc | No fix yet | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 8 | libvncserver +1 | 0.9.11-17.el8 | RHSA-2021:1811 |
AlmaLinux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux 8 | libvncserver +1 | 0.9.11-17.el8 | ALSA-2021:1811 |
Rocky Linux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Rocky Linux 8 | libvncserver | 0.9.11-17.el8 | RLSA-2021:1811 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP2 | LibVNCServer | 0.9.10-4.25.1 | SUSE-SU-2020:3515-1 |
| SLES 15 SP1 | LibVNCServer | 0.9.10-4.25.1 | SUSE-SU-2020:3515-1 |
| SLES 12 SP5 | LibVNCServer | 0.9.9-17.34.1 | SUSE-SU-2020:3550-1 |
| SLES 12 SP4 | LibVNCServer | 0.9.9-17.34.1 | SUSE-SU-2020:3550-1 |
| SLES 12 SP3 | LibVNCServer | 0.9.9-17.34.1 | SUSE-SU-2020:3550-1 |
Show 14 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 12 SP2 | LibVNCServer | 0.9.9-17.34.1 | SUSE-SU-2020:3550-1 |
| SLES 11 SP4 | LibVNCServer | 0.9.1-160.22.1 | SUSE-SU-2020:14549-1 |
| SLES for SAP 12 SP5 | LibVNCServer | 0.9.9-17.34.1 | SUSE-SU-2020:3550-1 |
| SLES for SAP 12 SP4 | LibVNCServer | 0.9.9-17.34.1 | SUSE-SU-2020:3550-1 |
| SLES for SAP 12 SP3 | LibVNCServer | 0.9.9-17.34.1 | SUSE-SU-2020:3550-1 |
| SLES for SAP 12 SP2 | LibVNCServer | 0.9.9-17.34.1 | SUSE-SU-2020:3550-1 |
| SUSE OpenStack Cloud Crowbar 9 | LibVNCServer | 0.9.9-17.34.1 | SUSE-SU-2020:3550-1 |
| SUSE OpenStack Cloud Crowbar 8 | LibVNCServer | 0.9.9-17.34.1 | SUSE-SU-2020:3550-1 |
| SUSE OpenStack Cloud 9 | LibVNCServer | 0.9.9-17.34.1 | SUSE-SU-2020:3550-1 |
| SUSE OpenStack Cloud 8 | LibVNCServer | 0.9.9-17.34.1 | SUSE-SU-2020:3550-1 |
| SUSE OpenStack Cloud 7 | LibVNCServer | 0.9.9-17.34.1 | SUSE-SU-2020:3550-1 |
| SUSE Linux Enterprise Point of Sale 11 SP3 | LibVNCServer | 0.9.1-160.22.1 | SUSE-SU-2020:14549-1 |
| SUSE HPE Helion OpenStack 8 | LibVNCServer | 0.9.9-17.34.1 | SUSE-SU-2020:3550-1 |
| SUSE Enterprise Storage 5 | LibVNCServer | 0.9.9-17.34.1 | SUSE-SU-2020:3550-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Leap 15.2 | LibVNCServer | 0.9.10-lp152.9.8.1 | openSUSE-SU-2020:2025-1 |
| openSUSE Leap 15.1 | LibVNCServer | 0.9.10-lp151.7.12.1 | openSUSE-SU-2020:2097-1 |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.24 | libvncserver | 0.9.13-r0 | — |
| Alpine v3.23 | libvncserver | 0.9.13-r0 | — |
| Alpine v3.22 | libvncserver | 0.9.13-r0 | — |
| Alpine v3.21 | libvncserver | 0.9.13-r0 | — |
| Alpine v3.20 | libvncserver | 0.9.13-r0 | — |
Show 8 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.19 | libvncserver | 0.9.13-r0 | — |
| Alpine v3.18 | libvncserver | 0.9.13-r0 | — |
| Alpine v3.17 | libvncserver | 0.9.13-r0 | — |
| Alpine v3.16 | libvncserver | 0.9.13-r0 | — |
| Alpine v3.15 | libvncserver | 0.9.13-r0 | — |
| Alpine v3.14 | libvncserver | 0.9.13-r0 | — |
| Alpine v3.13 | libvncserver | 0.9.13-r0 | — |
| Alpine v3.12 | libvncserver | 0.9.13-r0 | — |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 8 | libvncserver +1 | 0.9.11-17.el8 | ELSA-2021-1811 |
Advisories 12
- ALSA-2021:1811 Moderate: libvncserver security update AlmaLinux Security Advisories · Oct 29, 2026
- RHSA-2021:1811 Red Hat Security Advisory: libvncserver security update Red Hat Security Advisories (RHSA) · Jun 27, 2026
- USN-4636-1 libvncserver, vino vulnerability Ubuntu Security Notices (USN) · Apr 27, 2026
- DLA-3125-1 libvncserver - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DLA-2451-1 libvncserver - security update Debian Security (DSA / DLA) · Mar 9, 2026
- RLSA-2021:1811 Moderate: libvncserver security update Rocky Linux Security Advisories · Feb 4, 2026
- SUSE-SU-2020:14549-1 Security update for LibVNCServer SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2020:2097-1 Security update for LibVNCServer SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2020:2025-1 Security update for LibVNCServer SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2020:3550-1 Security update for LibVNCServer SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2020:3515-1 Security update for LibVNCServer SUSE / openSUSE Security Updates · Feb 4, 2026
- ELSA-2021-1811 Moderate: libvncserver security update (Oracle Linux 8) Oracle Linux Security Advisories (ELSA) · May 25, 2021