critical
CVE-2017-18922
libvncserver: websocket decoding buffer overflow
In the Trivy database since at least 24 Oct 2026, 07:11 UTCWhen it arrived before that build is not recorded.
Severity by source
NVD9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Red Hat9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Trivy's own label is CRITICAL. Rated critical by NVD. Rated lower by Red Hat (high), AlmaLinux (high), Oracle (high), Ubuntu (medium).
Description
It was discovered that websockets.c in LibVNCServer prior to 0.9.12 did not properly decode certain WebSocket frames. A malicious attacker could exploit this by sending specially crafted WebSocket frames to a server, causing a heap-based buffer overflow.
Affected packages and fixed versions
| Source | Package | Fixed in |
|---|---|---|
| alma 8 | libvncserver-devel | 0.9.11-15.el8_2.1 |
| debian 10 | libvncserver | no fix listed |
| debian 11 | libvncserver | 0.9.12+dfsg-3 |
| debian 12 | libvncserver | 0.9.12+dfsg-3 |
| debian 13 | libvncserver | 0.9.12+dfsg-3 |
| debian 14 | libvncserver | 0.9.12+dfsg-3 |
| debian 9 | libvncserver | no fix listed |
| echo | libvncserver | 0.9.12+dfsg-3 |
| Oracle Linux 7 | libvncserver, libvncserver-devel | 0.9.9-14.el7_8.1 |
| Oracle Linux 8 | libvncserver, libvncserver-devel | 0.9.11-15.el8_2.1 |
| ubuntu 16.04 | libvncserver | 0.9.10+dfsg-3ubuntu0.16.04.4 |
| ubuntu 16.04-ESM | libvncserver | 0.9.10+dfsg-3ubuntu0.16.04.4 |
Show all 19 entries from 17 sources
| Source | Package | Fixed in |
|---|---|---|
| alma 8 | libvncserver-devel | 0.9.11-15.el8_2.1 |
| debian 10 | libvncserver | no fix listed |
| debian 11 | libvncserver | 0.9.12+dfsg-3 |
| debian 12 | libvncserver | 0.9.12+dfsg-3 |
| debian 13 | libvncserver | 0.9.12+dfsg-3 |
| debian 14 | libvncserver | 0.9.12+dfsg-3 |
| debian 9 | libvncserver | no fix listed |
| echo | libvncserver | 0.9.12+dfsg-3 |
| Oracle Linux 7 | libvncserver | 0.9.9-14.el7_8.1 |
| Oracle Linux 7 | libvncserver-devel | 0.9.9-14.el7_8.1 |
| Oracle Linux 8 | libvncserver | 0.9.11-15.el8_2.1 |
| Oracle Linux 8 | libvncserver-devel | 0.9.11-15.el8_2.1 |
| ubuntu 16.04 | libvncserver | 0.9.10+dfsg-3ubuntu0.16.04.4 |
| ubuntu 16.04-ESM | libvncserver | 0.9.10+dfsg-3ubuntu0.16.04.4 |
| ubuntu 18.04 | libvncserver | 0.9.11+dfsg-1ubuntu1.2 |
| ubuntu 18.04-ESM | libvncserver | 0.9.11+dfsg-1ubuntu1.2 |
| ubuntu 19.10 | libvncserver | 0.9.11+dfsg-1.3ubuntu0.1 |
| ubuntu 20.04 | libvncserver | 0.9.12+dfsg-9ubuntu0.1 |
| ubuntu 20.04-ESM | libvncserver | 0.9.12+dfsg-9ubuntu0.1 |
References
- http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00020.html
- http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00028.html
- http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00033.html
- http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00055.html
- http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00066.html
- http://www.openwall.com/lists/oss-security/2020/06/30/3
- https://access.redhat.com/security/cve/CVE-2017-18922
- https://bugzilla.redhat.com/show_bug.cgi?id=1852356
All 19 references
- https://cert-portal.siemens.com/productcert/pdf/ssa-390195.pdf
- https://github.com/LibVNC/libvncserver/commit/aac95a9dcf4bbba87b76c72706c3221a842ca433
- https://linux.oracle.com/cve/CVE-2017-18922.html
- https://linux.oracle.com/errata/ELSA-2020-3385.html
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/4F6FUH4EFK4NAP6GT4TQRTBKWIRCZLIY/
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/NVP7TJVYJDXDFRHVQ3ENEN3H354QPXEZ/
- https://nvd.nist.gov/vuln/detail/CVE-2017-18922
- https://ubuntu.com/security/notices/USN-4407-1
- https://usn.ubuntu.com/4407-1/
- https://www.cve.org/CVERecord?id=CVE-2017-18922
- https://www.openwall.com/lists/oss-security/2020/06/30/2