CVE-2017-18922
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
02 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
03 Exploitation and scoring
- Exploitation
- Not assessed. CISA has not published an exploitation assessment for this record, and it is not in the KEV catalog. That is an absence of assessment, not a finding of no risk.
- SSVC decision
- Not assessed by CISA
- EPSS probability
- 2.25% probability of exploitation activity in the next 30 days.
- EPSS percentile
- Equal to or higher than the score of 82.4% of scored records. A rank, not a probability.
- NVD base score
- 9.8 (CVSS v3.x), scored by the NVD independently of the CNA.
- NVD CVSS vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- NVD analysis status
- Modified. NVD last modified this record on 2026-06-17.
- Red Hat severity
- Important. Red Hat's rating for its own products, not a CVSS rating.
Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.
04 Metadata
- Published
- 2020-06-30 11:00Z6 YR AGO
- Last updated
- 2024-08-05 21:45Z2 YR AGO
- Reserved
- 2020-06-30
- Assigning CNA
- mitre
- Record state
- PUBLISHED
- Severity
- Not rated by the issuing CNA
- CNA CVSS vector
- Not published by the issuing CNA
- Weaknesses
- Data version
- 5.1
- Document digest
- f5d45663702b14fb1e7f80372dda3db55448e024559d724c91ecabce0d3b8ec4
05 Affected products
06 References
- github.comhttps://github.com/LibVNC/libvncserver/commit/aac95a9dcf4bbba87b76c72706c3221a842ca433
- www.openwall.comhttps://www.openwall.com/lists/oss-security/2020/06/30/2
- bugzilla.redhat.comhttps://bugzilla.redhat.com/show_bug.cgi?id=1852356
- www.openwall.com[oss-security] 20200630 Re: libvncserver: old websocket decoding patchhttp://www.openwall.com/lists/oss-security/2020/06/30/3
- lists.opensuse.orgopenSUSE-SU-2020:0960http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00020.html
- lists.fedoraproject.orgFEDORA-2020-37112ac660https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/NVP7TJVYJDXDFRHVQ3ENEN3H354QPXEZ/
- usn.ubuntu.comUSN-4407-1https://usn.ubuntu.com/4407-1/
- lists.fedoraproject.orgFEDORA-2020-1a4b1c8271https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4F6FUH4EFK4NAP6GT4TQRTBKWIRCZLIY/
- lists.opensuse.orgopenSUSE-SU-2020:0978http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00028.html
- lists.opensuse.orgopenSUSE-SU-2020:0988http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00033.html
- lists.opensuse.orgopenSUSE-SU-2020:1025http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00055.html
- lists.opensuse.orgopenSUSE-SU-2020:1056http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00066.html
- cert-portal.siemens.comhttps://cert-portal.siemens.com/productcert/pdf/ssa-390195.pdf
07 Fixed in
AlmaLinux 8
- libvncserver-devel Fixed in 0.9.11-15.el8_2.1
Source: AlmaLinux, AlmaLinux OS. Copyright (c) 2023 AlmaLinux OS. Licensed under MIT License. Received through OSV.dev. Reformatted by exploit.cc.
CloudLinux 8
- libvncserver-devel Fixed in 0.9.11-15.el8_2.1
Derived from AlmaLinux 8. Partial coverage: only packages taken from AlmaLinux 8 are listed.
Source: CloudLinux errata, CloudLinux Inc. Derived from: AlmaLinux, AlmaLinux OS. Copyright (c) 2023 AlmaLinux OS. Licensed under MIT License. Received through OSV.dev. Reformatted by exploit.cc.
Debian 12
- libvncserver Fixed in 0.9.12+dfsg-3
Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.
Debian 13
- libvncserver Fixed in 0.9.12+dfsg-3
Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.
Debian 14
- libvncserver Fixed in 0.9.12+dfsg-3
Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 14.04 LTS
- x11vnc No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 16.04 LTS
- libvncserver Fixed in 0.9.10+dfsg-3ubuntu0.16.04.4
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 18.04 LTS
- libvncserver Fixed in 0.9.11+dfsg-1ubuntu1.2
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 20.04 LTS
- libvncserver Fixed in 0.9.12+dfsg-9ubuntu0.1
- veyon No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 22.04 LTS
- veyon No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 24.04 LTS
- veyon No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 25.10
- veyon No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 26.04 LTS
- veyon No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 26.10
- veyon No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
A release or ecosystem missing from this list has no record here. It may be unaffected or not covered by the source. Source notices and licences.