Description
The VNC websocket frame decoder in QEMU allows remote attackers to cause a denial of service (memory and CPU consumption) via a large (1) websocket payload or (2) HTTP headers section.
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 | qemu | 1:2.3+dfsg-1 | — |
| Debian 13 | qemu | 1:2.3+dfsg-1 | — |
| Debian 12 | qemu | 1:2.3+dfsg-1 | — |
| Debian 8 | qemu | 1:2.1+dfsg-12 | DSA-3259-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 14.04 LTS | qemu | 2.0.0+dfsg-2ubuntu1.11 | USN-2608-1 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 7 | qemu-img +6 | 10:1.5.3-86.el7_1.8 | RHSA-2015:1943 |
| RHEL 7 | qemu-img-rhev +6 | 10:2.1.2-23.el7_1.10 | RHSA-2015:1931 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 12 SP1 | xen | 4.5.2_06-7.1 | SUSE-SU-2016:0873-1 |
| SLES 12 | qemu | 2.0.2-46.1 | SUSE-SU-2015:0896-1 |
| SLES 12 | xen | 4.4.4_02-22.19.1 | SUSE-SU-2016:1318-1 |
| SLES 11 SP4 | kvm | 1.4.2-60.34.1 | SUSE-SU-2021:14704-1 |
| SLES 11 SP4 | xen | 4.4.4_02-32.1 | SUSE-SU-2016:0955-1 |
Show 4 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 12 SP1 | xen | 4.5.2_06-7.1 | SUSE-SU-2016:0873-1 |
| SLES for SAP 12 | qemu | 2.0.2-46.1 | SUSE-SU-2015:0896-1 |
| SLES for SAP 12 | xen | 4.4.4_02-22.19.1 | SUSE-SU-2016:1318-1 |
| SLES for SAP 11 SP4 | xen | 4.4.4_02-32.1 | SUSE-SU-2016:0955-1 |
| SUSE Linux Enterprise Point of Sale 11 SP3 | kvm | 1.4.2-53.38.1 | SUSE-SU-2021:14706-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | xen | 4.7.0_12-1.3 | openSUSE-SU-2024:10196-1 |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 7 | qemu-img +6 | 10:1.5.3-86.el7_1.8 | ELSA-2015-1943 |
Advisories 12
- RHSA-2015:1931 Red Hat Security Advisory: qemu-kvm-rhev security update Red Hat Security Advisories (RHSA) · Jun 29, 2026
- RHSA-2015:1943 Red Hat Security Advisory: qemu-kvm security update Red Hat Security Advisories (RHSA) · Jun 29, 2026
- DSA-3259-1 qemu - security update Debian Security (DSA / DLA) · Mar 9, 2026
- USN-2608-1 qemu, qemu-kvm vulnerabilities Ubuntu Security Notices (USN) · Feb 10, 2026
- SUSE-SU-2016:1318-1 Security update for xen SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2021:14704-1 Security update for kvm SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2016:0955-1 Security update for xen SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2021:14706-1 Security update for kvm SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2015:0896-1 Security update for qemu SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:10196-1 xen-4.7.0_12-1.3 on GA media SUSE / openSUSE Security Updates · May 7, 2025
- SUSE-SU-2016:0873-1 Security update for xen SUSE / openSUSE Security Updates · May 2, 2025
- ELSA-2015-1943 Moderate: qemu-kvm security update (Oracle Linux 7) Oracle Linux Security Advisories (ELSA) · Oct 27, 2015
References
- SUSE-SU-2015:0870 vendor-advisory
- [Qemu-devel] 20150323 [PATCH 1/2] CVE-2015-1779: incrementally decode websocket frames mailing-list
- FEDORA-2015-5541 vendor-advisory
- DSA-3259 vendor-advisory
- [oss-security] 20150409 Re: CVE-2015-1779 qemu: vnc: insufficient resource limiting in VNC websockets decoder mailing-list
- SUSE-SU-2015:0896 vendor-advisory
- FEDORA-2015-5482 vendor-advisory
- [Qemu-devel] 20150323 [PATCH 0/2] CVE-2015-1779: fix denial of service in VNC websockets mailing-list
- RHSA-2015:1931 vendor-advisory
- [oss-security] 20150324 CVE-2015-1779 qemu: vnc: insufficient resource limiting in VNC websockets decoder mailing-list
- 1033975 vdb-entry
- http://www.oracle.com/technetwork/topics/security/linuxbulletinoct2015-2719645.html
- RHSA-2015:1943 vendor-advisory
- USN-2608-1 vendor-advisory
- [Qemu-devel] 20150323 [PATCH 2/2] CVE-2015-1779: limit size of HTTP headers from websockets clients mailing-list
- 73303 vdb-entry
- GLSA-201602-01 vendor-advisory