CVE-2019-20840
published 2020-06-17CVE-2019-20840: An issue was discovered in LibVNCServer before 0.9.13. libvncserver/ws_decode.c can lead to a crash because of unaligned accesses in hybiReadAndDecode.
PriorityP337high7.5CVSS 3.1
AVNACLPRNUINSUCNINAH
EPSS
2.59%
83.5th percentile
An issue was discovered in LibVNCServer before 0.9.13. libvncserver/ws_decode.c can lead to a crash because of unaligned accesses in hybiReadAndDecode.
Affected
23 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| canonical | ubuntu_linux | — | — |
| canonical | ubuntu_linux | — | — |
| canonical | ubuntu_linux | — | — |
| canonical | ubuntu_linux | — | — |
| canonical | ubuntu_linux | — | — |
| debian | debian_linux | — | — |
| debian | debian_linux | — | — |
| debian | libvncserver | < libvncserver 0.9.13+dfsg-1 (bookworm) | libvncserver 0.9.13+dfsg-1 (bookworm) |
| libvnc_project | libvncserver | <= 0.9.12 | — |
| libvncserver_project | libvncserver | >= 0 < 0.9.13+dfsg-1 | 0.9.13+dfsg-1 |
| libvncserver_project | libvncserver | >= 0 < 0.9.13+dfsg-1 | 0.9.13+dfsg-1 |
| libvncserver_project | libvncserver | >= 0 < 0.9.13+dfsg-1 | 0.9.13+dfsg-1 |
| libvncserver_project | libvncserver | >= 0 < 0.9.13+dfsg-1 | 0.9.13+dfsg-1 |
| libvncserver_project | libvncserver | >= 0 < 0.9.10+dfsg-3ubuntu0.16.04.5 | 0.9.10+dfsg-3ubuntu0.16.04.5 |
| libvncserver_project | libvncserver | >= 0 < 0.9.11+dfsg-1ubuntu1.3 | 0.9.11+dfsg-1ubuntu1.3 |
| libvncserver_project | libvncserver | >= 0 < 0.9.12+dfsg-9ubuntu0.2 | 0.9.12+dfsg-9ubuntu0.2 |
| opensuse | leap | — | — |
| siemens | simatic_itc1500_firmware | >= 3.0.0.0 < 3.2.1.0 | 3.2.1.0 |
| siemens | simatic_itc1500_pro_firmware | >= 3.0.0.0 < 3.2.1.0 | 3.2.1.0 |
| siemens | simatic_itc1900_firmware | >= 3.0.0.0 < 3.2.1.0 | 3.2.1.0 |
| siemens | simatic_itc1900_pro_firmware | >= 3.0.0.0 < 3.2.1.0 | 3.2.1.0 |
| siemens | simatic_itc2200_firmware | >= 3.0.0.0 < 3.2.1.0 | 3.2.1.0 |
| siemens | simatic_itc2200_pro_firmware | >= 3.0.0.0 < 3.2.1.0 | 3.2.1.0 |
CVSS provenance
nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
nvdv2.05.0MEDIUMAV:N/AC:L/Au:N/C:N/I:N/A:P
osv7.5HIGH
vendor_debian7.5HIGH
vendor_redhat7.5HIGH
vendor_ubuntu7.5HIGH
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GHSA
GHSA-42fc-843w-r7rp: An issue was discovered in LibVNCServer before 0
ghsa_unreviewed·2022-05-24
CVE-2019-20840 [MEDIUM] CWE-119 GHSA-42fc-843w-r7rp: An issue was discovered in LibVNCServer before 0
An issue was discovered in LibVNCServer before 0.9.13. libvncserver/ws_decode.c can lead to a crash because of unaligned accesses in hybiReadAndDecode.
OSV
libvncserver vulnerabilities
osv·2020-07-23·CVSS 7.5
CVE-2019-20839 [HIGH] libvncserver vulnerabilities
libvncserver vulnerabilities
Ramin Farajpour Cami discovered that LibVNCServer incorrectly handled
certain malformed unix socket names. A remote attacker could exploit this
with a crafted socket name, leading to a denial of service, or possibly
execute arbitrary code. (CVE-2019-20839)
It was discovered that LibVNCServer did not properly access byte-aligned
data. A remote attacker could possibly use this issue to cause
LibVNCServer to crash, resulting in a denial of service. This issue only
affected Ubuntu 18.04 LTS and Ubuntu 16.04 LTS. (CVE-2019-20840)
Christian Beier discovered that LibVNCServer incorrectly handled anonymous
TLS connections. A remote attacker could possibly use this issue to cause
LibVNCServer to crash, resulting in a denial of service. This issue only
affected Ubuntu
OSV
CVE-2019-20840: An issue was discovered in LibVNCServer before 0
osv·2020-06-17·CVSS 7.5
CVE-2019-20840 [HIGH] CVE-2019-20840: An issue was discovered in LibVNCServer before 0
An issue was discovered in LibVNCServer before 0.9.13. libvncserver/ws_decode.c can lead to a crash because of unaligned accesses in hybiReadAndDecode.
CISA ICS
Siemens SIMATIC ITC
cisa_ics·2021-12-16·CVSS 9.8
[CRITICAL] Siemens SIMATIC ITC
## Archived Content In an effort to keep CISA.gov current, the archive contains outdated information that may not reflect current policy or programs.
ICS Advisory
##
Siemens SIMATIC ITC
Last RevisedDecember 16, 2021
Alert CodeICSA-21-350-12
## 1. EXECUTIVE SUMMARY
- CVSS v3 9.8
- ATTENTION: Exploitable remotely/low attack complexity
- Vendor: Siemens
- Equipment: SIMATIC ITC Products
- Vulnerabilities: Using Components with Known Vulnerabilities
## 2. RISK EVALUATION
Successful exploitation of these LibVNC vulnerabilities could allow remote code execution, information disclosure, and denial-of-service attacks.
## 3. TECHNICAL DETAILS
## 3.1 AFFECTED PRODUCTS
Siemens reports these vulnerabilities affect the following SIMATIC Industri
Ubuntu
LibVNCServer vulnerabilities
vendor_ubuntu·2020-07-23·CVSS 7.5
CVE-2019-20839 [HIGH] LibVNCServer vulnerabilities
Title: LibVNCServer vulnerabilities
Summary: Several security issues were fixed in LibVNCServer.
Ramin Farajpour Cami discovered that LibVNCServer incorrectly handled
certain malformed unix socket names. A remote attacker could exploit this
with a crafted socket name, leading to a denial of service, or possibly
execute arbitrary code. (CVE-2019-20839)
It was discovered that LibVNCServer did not properly access byte-aligned
data. A remote attacker could possibly use this issue to cause
LibVNCServer to crash, resulting in a denial of service. This issue only
affected Ubuntu 18.04 LTS and Ubuntu 16.04 LTS. (CVE-2019-20840)
Christian Beier discovered that LibVNCServer incorrectly handled anonymous
TLS connections. A remote attacker could possibly use this issue to cause
LibVNCServer to cra
Red Hat
libvncserver: unaligned accesses in hybiReadAndDecode can lead to a crash
vendor_redhat·2020-06-17·CVSS 7.5
CVE-2019-20840 [HIGH] CWE-119 libvncserver: unaligned accesses in hybiReadAndDecode can lead to a crash
libvncserver: unaligned accesses in hybiReadAndDecode can lead to a crash
An issue was discovered in LibVNCServer before 0.9.13. libvncserver/ws_decode.c can lead to a crash because of unaligned accesses in hybiReadAndDecode.
Package: libvncserver (Red Hat Enterprise Linux 6) - Not affected
Package: libvncserver (Red Hat Enterprise Linux 7) - Not affected
Package: libvncserver (Red Hat Enterprise Linux 8) - Not affected
Debian
CVE-2019-20840: libvncserver - An issue was discovered in LibVNCServer before 0.9.13. libvncserver/ws_decode.c ...
vendor_debian·2019·CVSS 7.5
CVE-2019-20840 [HIGH] CVE-2019-20840: libvncserver - An issue was discovered in LibVNCServer before 0.9.13. libvncserver/ws_decode.c ...
An issue was discovered in LibVNCServer before 0.9.13. libvncserver/ws_decode.c can lead to a crash because of unaligned accesses in hybiReadAndDecode.
Scope: local
bookworm: resolved (fixed in 0.9.13+dfsg-1)
bullseye: resolved (fixed in 0.9.13+dfsg-1)
forky: resolved (fixed in 0.9.13+dfsg-1)
sid: resolved (fixed in 0.9.13+dfsg-1)
trixie: resolved (fixed in 0.9.13+dfsg-1)
No detection rules found.
No public exploits indexed.
Bugzilla
CVE-2019-20840 libvncserver: unaligned accesses in hybiReadAndDecode can lead to a crash [epel-7]
bugzilla·2020-06-23·CVSS 7.5
CVE-2019-20840 [HIGH] CVE-2019-20840 libvncserver: unaligned accesses in hybiReadAndDecode can lead to a crash [epel-7]
CVE-2019-20840 libvncserver: unaligned accesses in hybiReadAndDecode can lead to a crash [epel-7]
This is an automatically created tracking bug! It was created to ensure
that one or more security vulnerabilities are fixed in affected versions
of epel-7.
For comments that are specific to the vulnerability please use bugs filed
against the "Security Response" product referenced in the "Blocks" field.
For more information see:
http://fedoraproject.org/wiki/Security/TrackingBugs
When submitting as an update, use the fedpkg template provided in the next
comment(s). This will include the bug IDs of this tracking bug as well as
the relevant top-level CVE bugs.
Please also mention the CVE IDs being fixed in the RPM changelog and the
fedpkg commit message.
Discussion:
Use the following templ
Bugzilla
CVE-2019-20840 libvncserver: unaligned accesses in hybiReadAndDecode can lead to a crash [fedora-all]
bugzilla·2020-06-23·CVSS 7.5
CVE-2019-20840 [HIGH] CVE-2019-20840 libvncserver: unaligned accesses in hybiReadAndDecode can lead to a crash [fedora-all]
CVE-2019-20840 libvncserver: unaligned accesses in hybiReadAndDecode can lead to a crash [fedora-all]
This is an automatically created tracking bug! It was created to ensure
that one or more security vulnerabilities are fixed in affected versions
of fedora-all.
For comments that are specific to the vulnerability please use bugs filed
against the "Security Response" product referenced in the "Blocks" field.
For more information see:
http://fedoraproject.org/wiki/Security/TrackingBugs
When submitting as an update, use the fedpkg template provided in the next
comment(s). This will include the bug IDs of this tracking bug as well as
the relevant top-level CVE bugs.
Please also mention the CVE IDs being fixed in the RPM changelog and the
fedpkg commit message.
NOTE: this issue affects mul
Bugzilla
CVE-2019-20840 libvncserver: unaligned accesses in hybiReadAndDecode can lead to a crash
bugzilla·2020-06-23·CVSS 7.5
CVE-2019-20840 [HIGH] CVE-2019-20840 libvncserver: unaligned accesses in hybiReadAndDecode can lead to a crash
CVE-2019-20840 libvncserver: unaligned accesses in hybiReadAndDecode can lead to a crash
An issue was discovered in LibVNCServer before 0.9.13. libvncserver/ws_decode.c can lead to a crash because of unaligned accesses in hybiReadAndDecode.
Upstream Reference:
https://github.com/LibVNC/libvncserver/commit/0cf1400c61850065de590d403f6d49e32882fd76
Discussion:
Created libvncserver tracking bugs for this issue:
Affects: epel-7 [bug 1849883]
Affects: fedora-all [bug 1849882]
---
This bug is now closed. Further updates for individual products will be reflected on the CVE page(s):
https://access.redhat.com/security/cve/cve-2019-20840
http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00033.htmlhttp://lists.opensuse.org/opensuse-security-announce/2020-07/msg00055.htmlhttp://lists.opensuse.org/opensuse-security-announce/2020-07/msg00066.htmlhttps://cert-portal.siemens.com/productcert/pdf/ssa-390195.pdfhttps://github.com/LibVNC/libvncserver/commit/0cf1400c61850065de590d403f6d49e32882fd76https://github.com/LibVNC/libvncserver/compare/LibVNCServer-0.9.12...LibVNCServer-0.9.13https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4F6FUH4EFK4NAP6GT4TQRTBKWIRCZLIY/https://usn.ubuntu.com/4434-1/http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00033.htmlhttp://lists.opensuse.org/opensuse-security-announce/2020-07/msg00055.htmlhttp://lists.opensuse.org/opensuse-security-announce/2020-07/msg00066.htmlhttps://cert-portal.siemens.com/productcert/pdf/ssa-390195.pdfhttps://github.com/LibVNC/libvncserver/commit/0cf1400c61850065de590d403f6d49e32882fd76https://github.com/LibVNC/libvncserver/compare/LibVNCServer-0.9.12...LibVNCServer-0.9.13https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4F6FUH4EFK4NAP6GT4TQRTBKWIRCZLIY/https://usn.ubuntu.com/4434-1/
2020-06-17
Published