Description
The HandleRFBServerMessage function in libvncclient/rfbproto.c in LibVNCServer 0.9.9 and earlier does not check certain malloc return values, which allows remote VNC servers to cause a denial of service (application crash) or possibly execute arbitrary code by specifying a large screen size in a (1) FramebufferUpdate, (2) ResizeFrameBuffer, or (3) PalmVNCReSizeFrameBuffer message.
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 | 0.9.9+dfsg-6.1 | — |
| Debian 13 | libvncserver | 0.9.9+dfsg-6.1 | — |
| Debian 13 | veyon | 4.1.4+repack1-1 | — |
| Debian 12 | libvncserver | 0.9.9+dfsg-6.1 | — |
| Debian 12 | veyon | 4.1.4+repack1-1 | — |
| Debian 8 | italc | 1:2.0.2+dfsg1-2+deb8u1 | DLA-1979-1 |
| Debian 7 | libvncserver | 0.9.9+dfsg-1+deb7u1 | DSA-3081-1 |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 6.0 | libvncserver | 0.9.7-2+deb6u1 | DLA-197-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 16.04 LTS | italc | 1:2.0.2+dfsg1-4ubuntu0.1 | USN-4587-1 |
| Ubuntu 14.04 LTS | libvncserver | 0.9.9+dfsg-1ubuntu1.1 | USN-2365-1 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 7 | libvncserver +1 | 0.9.9-9.el7_0.1 | RHSA-2014:1826 |
| RHEL 6 | libvncserver +1 | 0.9.7-7.el6_6.1 | RHSA-2014:1826 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 12 SP1 | LibVNCServer | 0.9.9-16.1 | SUSE-SU-2015:2088-2 |
| SLES 12 | LibVNCServer | 0.9.9-16.1 | SUSE-SU-2015:2088-1 |
| SLES 11 SP4 | LibVNCServer | 0.9.1-156.1 | SUSE-SU-2015:2110-1 |
| SLES 11 SP3 | LibVNCServer | 0.9.1-156.1 | SUSE-SU-2015:2110-1 |
Show 4 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 12 SP1 | LibVNCServer | 0.9.9-16.1 | SUSE-SU-2015:2088-2 |
| SLES for SAP 12 | LibVNCServer | 0.9.9-16.1 | SUSE-SU-2015:2088-1 |
| SLES for SAP 11 SP4 | LibVNCServer | 0.9.1-156.1 | SUSE-SU-2015:2110-1 |
| SLES for SAP 11 SP3 | LibVNCServer | 0.9.1-156.1 | SUSE-SU-2015:2110-1 |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 7 | libvncserver +1 | 0.9.9-9.el7_0.1 | ELSA-2014-1826 |
Advisories 10
- RHSA-2014:1826 Red Hat Security Advisory: libvncserver security update Red Hat Security Advisories (RHSA) · Jun 28, 2026
- USN-4587-1 italc vulnerabilities Ubuntu Security Notices (USN) · Apr 27, 2026
- USN-2365-1 libvncserver vulnerabilities Ubuntu Security Notices (USN) · Apr 27, 2026
- DLA-197-1 libvncserver - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DSA-3081-1 libvncserver - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DLA-1979-1 italc - security update Debian Security (DSA / DLA) · Mar 9, 2026
- SUSE-SU-2015:2088-1 Security update for LibVNCServer SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2015:2088-2 Security update for LibVNCServer SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2015:2110-1 Security update for LibVNCServer SUSE / openSUSE Security Updates · Feb 4, 2026
- ELSA-2014-1826 Moderate: libvncserver security update (Oracle Linux 7) Oracle Linux Security Advisories (ELSA) · Nov 11, 2014
References
- http://www.ocert.org/advisories/ocert-2014-007.html
- 61682 third-party-advisory
- openSUSE-SU-2015:2207 vendor-advisory
- 61506 third-party-advisory
- https://github.com/newsoft/libvncserver/commit/85a778c0e45e87e35ee7199f1f25020648e8b812
- [oss-security] 20140925 [oCERT-2014-007] libvncserver multiple issues mailing-list
- [oss-security] 20140923 Multiple issues in libVNCserver mailing-list
- USN-2365-1 vendor-advisory
- GLSA-201507-07 vendor-advisory
- 70091 vdb-entry
- DSA-3081 vendor-advisory
- http://www.oracle.com/technetwork/topics/security/bulletinoct2015-2511968.html
- [debian-lts-announce] 20191030 [SECURITY] [DLA 1979-1] italc security update mailing-list
- USN-4587-1 vendor-advisory