CVE-2018-20020
published 2018-12-19CVE-2018-20020: LibVNC before commit 7b1ef0ffc4815cab9a96c7278394152bdc89dc4d contains heap out-of-bound write vulnerability inside structure in VNC client code that can…
PriorityP259critical9.8CVSS 3.0
AVNACLPRNUINSUCHIHAH
EPSS
8.55%
94.4th percentile
LibVNC before commit 7b1ef0ffc4815cab9a96c7278394152bdc89dc4d contains heap out-of-bound write vulnerability inside structure in VNC client code that can result remote code execution
Affected
14 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| canonical | ubuntu_linux | — | — |
| canonical | ubuntu_linux | — | — |
| canonical | ubuntu_linux | — | — |
| canonical | ubuntu_linux | — | — |
| debian | debian_linux | — | — |
| debian | debian_linux | — | — |
| debian | libvncserver | < libvncserver 0.9.11+dfsg-1.2 (bookworm) | libvncserver 0.9.11+dfsg-1.2 (bookworm) |
| debian | ssvnc | < libvncserver 0.9.11+dfsg-1.2 (bookworm) | libvncserver 0.9.11+dfsg-1.2 (bookworm) |
| debian | veyon | < libvncserver 0.9.11+dfsg-1.2 (bookworm) | libvncserver 0.9.11+dfsg-1.2 (bookworm) |
| libvnc_project | libvncserver | < 0.9.12 | 0.9.12 |
| libvncserver_project | libvncserver | >= 0 < 0.9.11+dfsg-1.2 | 0.9.11+dfsg-1.2 |
| libvncserver_project | libvncserver | >= 0 < 0.9.11+dfsg-1.2 | 0.9.11+dfsg-1.2 |
| libvncserver_project | libvncserver | >= 0 < 0.9.11+dfsg-1.2 | 0.9.11+dfsg-1.2 |
| libvncserver_project | libvncserver | >= 0 < 0.9.11+dfsg-1.2 | 0.9.11+dfsg-1.2 |
Detection & IOCsextracted from sources · hover to see the quote
- →The vulnerability is a heap out-of-bound write in the VNC client code (LibVNCClient). Monitor VNC client processes (e.g. ssvnc, libvncserver-based clients) for anomalous heap corruption or crashes when connecting to untrusted VNC servers. ↗
- →The vulnerability is triggered by a remote (server-side) attacker sending malformed packet lengths to a connecting VNC client. Inspect VNC traffic (default port 5900) for malformed or oversized structure fields sent from server to client. ↗
- →Check installed libvncserver / libvncclient package versions; any version prior to the fix commit 7b1ef0ffc4815cab9a96c7278394152bdc89dc4d is vulnerable. On Debian/Ubuntu, the fixed package version is 0.9.11+dfsg-1.2. ↗
- ·Red Hat Enterprise Linux 6, 7, and 8 are marked 'Will not fix' for this CVE; patching via official RHEL channels is not available. ↗
CVSS provenance
nvdv3.09.8CRITICALCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
nvdv2.07.5HIGHAV:N/AC:L/Au:N/C:P/I:P/A:P
osv9.8CRITICAL
vendor_debian9.8CRITICAL
vendor_redhat9.8CRITICAL
vendor_ubuntu9.8CRITICAL
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GHSA
GHSA-v93r-hw5v-g7wc: LibVNC before commit 7b1ef0ffc4815cab9a96c7278394152bdc89dc4d contains heap out-of-bound write vulnerability inside structure in VNC client code that
ghsa_unreviewed·2022-05-13
CVE-2018-20020 [CRITICAL] CWE-787 GHSA-v93r-hw5v-g7wc: LibVNC before commit 7b1ef0ffc4815cab9a96c7278394152bdc89dc4d contains heap out-of-bound write vulnerability inside structure in VNC client code that
LibVNC before commit 7b1ef0ffc4815cab9a96c7278394152bdc89dc4d contains heap out-of-bound write vulnerability inside structure in VNC client code that can result remote code execution
OSV
italc vulnerabilities
osv·2020-10-20·CVSS 7.5
CVE-2014-6051 [HIGH] italc vulnerabilities
italc vulnerabilities
Nicolas Ruff discovered that iTALC had buffer overflows, divide-by-zero errors
and didn't check malloc return values. A remote attacker could use these issues
to cause a denial of service or possibly execute arbitrary code.
(CVE-2014-6051, CVE-2014-6052, CVE-2014-6053, CVE-2014-6054, CVE-2014-6055)
Josef Gajdusek discovered that iTALC had heap-based buffer overflow
vulnerabilities. A remote attacker could used these issues to cause a denial of
service or possibly execute arbitrary code. (CVE-2016-9941, CVE-2016-9942)
It was discovered that iTALC had an out-of-bounds write, multiple heap
out-of-bounds writes, an infinite loop, improper initializations, and null
pointer vulnerabilities. A remote attacker could used these issues to cause a
denial of service or possibl
OSV
ssvnc vulnerabilities
osv·2020-09-28·CVSS 9.8
CVE-2018-20020 [CRITICAL] ssvnc vulnerabilities
ssvnc vulnerabilities
It was discovered that the LibVNCClient vendored in SSVNC incorrectly handled
certain packet lengths. A remote attacker could possibly use this issue to
obtain sensitive information, cause a denial of service, or execute arbitrary
code. (CVE-2018-20020, CVE-2018-20021, CVE-2018-20022, CVE-2018-2024)
OSV
italc vulnerabilities
osv·2020-09-28·CVSS 9.8
CVE-2019-15681 [CRITICAL] italc vulnerabilities
italc vulnerabilities
It was discovered that an information disclosure vulnerability existed in the
LibVNCServer vendored in iTALC when sending a ServerCutText message. An
attacker could possibly use this issue to expose sensitive information.
(CVE-2019-15681)
It was discovered that the LibVNCServer and LibVNCClient vendored in iTALC
incorrectly handled certain packet lengths. A remote attacker could possibly
use this issue to obtain sensitive information, cause a denial of service, or
execute arbitrary code.
(CVE-2018-15127 CVE-2018-20019, CVE-2018-20020, CVE-2018-20021, CVE-2018-20022,
CVE-2018-20023, CVE-2018-20024, CVE-2018-20748, CVE-2018-20749, CVE-2018-20750,
CVE-2018-7225, CVE-2019-15681)
OSV
CVE-2018-20020: LibVNC before commit 7b1ef0ffc4815cab9a96c7278394152bdc89dc4d contains heap out-of-bound write vulnerability inside structure in VNC client code that
osv·2018-12-19·CVSS 9.8
CVE-2018-20020 [CRITICAL] CVE-2018-20020: LibVNC before commit 7b1ef0ffc4815cab9a96c7278394152bdc89dc4d contains heap out-of-bound write vulnerability inside structure in VNC client code that
LibVNC before commit 7b1ef0ffc4815cab9a96c7278394152bdc89dc4d contains heap out-of-bound write vulnerability inside structure in VNC client code that can result remote code execution
Ubuntu
iTALC vulnerabilities
vendor_ubuntu·2020-10-20·CVSS 7.5
CVE-2018-20749 [HIGH] iTALC vulnerabilities
Title: iTALC vulnerabilities
Summary: Several security issues were fixed in iTALC.
Nicolas Ruff discovered that iTALC had buffer overflows, divide-by-zero errors
and didn't check malloc return values. A remote attacker could use these issues
to cause a denial of service or possibly execute arbitrary code.
(CVE-2014-6051, CVE-2014-6052, CVE-2014-6053, CVE-2014-6054, CVE-2014-6055)
Josef Gajdusek discovered that iTALC had heap-based buffer overflow
vulnerabilities. A remote attacker could used these issues to cause a denial of
service or possibly execute arbitrary code. (CVE-2016-9941, CVE-2016-9942)
It was discovered that iTALC had an out-of-bounds write, multiple heap
out-of-bounds writes, an infinite loop, improper initializations, and null
pointer vulnerabilities. A remote attacker c
Ubuntu
iTALC vulnerabilities
vendor_ubuntu·2020-09-28·CVSS 9.8
CVE-2018-15127 [CRITICAL] iTALC vulnerabilities
Title: iTALC vulnerabilities
Summary: Several security issues were fixed in iTALC.
It was discovered that an information disclosure vulnerability existed in the
LibVNCServer vendored in iTALC when sending a ServerCutText message. An
attacker could possibly use this issue to expose sensitive information.
(CVE-2019-15681)
It was discovered that the LibVNCServer and LibVNCClient vendored in iTALC
incorrectly handled certain packet lengths. A remote attacker could possibly
use this issue to obtain sensitive information, cause a denial of service, or
execute arbitrary code.
(CVE-2018-15127 CVE-2018-20019, CVE-2018-20020, CVE-2018-20021, CVE-2018-20022,
CVE-2018-20023, CVE-2018-20024, CVE-2018-20748, CVE-2018-20749, CVE-2018-20750,
CVE-2018-7225, CVE-2019-15681)
Instructions: In general, a s
Ubuntu
SSVNC vulnerabilities
vendor_ubuntu·2020-09-28·CVSS 9.8
CVE-2018-20020 [CRITICAL] SSVNC vulnerabilities
Title: SSVNC vulnerabilities
Summary: Several security issues were fixed in SSVNC.
It was discovered that the LibVNCClient vendored in SSVNC incorrectly handled
certain packet lengths. A remote attacker could possibly use this issue to
obtain sensitive information, cause a denial of service, or execute arbitrary
code. (CVE-2018-20020, CVE-2018-20021, CVE-2018-20022, CVE-2018-2024)
Instructions: In general, a standard system update will make all the necessary changes.
Ubuntu
LibVNCServer vulnerabilities
vendor_ubuntu·2019-01-31
CVE-2018-15126 LibVNCServer vulnerabilities
Title: LibVNCServer vulnerabilities
Summary: Several security issues were fixed in LibVNCServer.
It was discovered that LibVNCServer incorrectly handled certain operations.
A remote attacker able to connect to applications using LibVNCServer could
possibly use this issue to obtain sensitive information, cause a denial of
service, or execute arbitrary code.
Instructions: After a standard system update you need to restart LibVNCServer
applications to make all the necessary changes.
Red Hat
libvncserver: Heap out-of-bound write inside structure in VNC client code allows for potential code execution
vendor_redhat·2018-12-19·CVSS 9.8
CVE-2018-20020 [CRITICAL] CWE-416 libvncserver: Heap out-of-bound write inside structure in VNC client code allows for potential code execution
libvncserver: Heap out-of-bound write inside structure in VNC client code allows for potential code execution
LibVNC before commit 7b1ef0ffc4815cab9a96c7278394152bdc89dc4d contains heap out-of-bound write vulnerability inside structure in VNC client code that can result remote code execution
Package: libvncserver (Red Hat Enterprise Linux 6) - Will not fix
Package: libvncserver (Red Hat Enterprise Linux 7) - Will not fix
Package: libvncserver (Red Hat Enterprise Linux 8) - Will not fix
Debian
CVE-2018-20020: libvncserver - LibVNC before commit 7b1ef0ffc4815cab9a96c7278394152bdc89dc4d contains heap out-...
vendor_debian·2018·CVSS 9.8
CVE-2018-20020 [CRITICAL] CVE-2018-20020: libvncserver - LibVNC before commit 7b1ef0ffc4815cab9a96c7278394152bdc89dc4d contains heap out-...
LibVNC before commit 7b1ef0ffc4815cab9a96c7278394152bdc89dc4d contains heap out-of-bound write vulnerability inside structure in VNC client code that can result remote code execution
Scope: local
bookworm: resolved (fixed in 0.9.11+dfsg-1.2)
bullseye: resolved (fixed in 0.9.11+dfsg-1.2)
forky: resolved (fixed in 0.9.11+dfsg-1.2)
sid: resolved (fixed in 0.9.11+dfsg-1.2)
trixie: resolved (fixed in 0.9.11+dfsg-1.2)
No detection rules found.
No public exploits indexed.
Bugzilla
CVE-2018-20020 libvncserver: Heap out-of-bound write inside structure in VNC client code allows for potential code execution [epel-7]
bugzilla·2018-12-20·CVSS 9.8
CVE-2018-20020 [CRITICAL] CVE-2018-20020 libvncserver: Heap out-of-bound write inside structure in VNC client code allows for potential code execution [epel-7]
CVE-2018-20020 libvncserver: Heap out-of-bound write inside structure in VNC client code allows for potential code execution [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.
Bugzilla
CVE-2018-20020 libvncserver: Heap out-of-bound write inside structure in VNC client code allows for potential code execution
bugzilla·2018-12-20·CVSS 9.8
CVE-2018-20020 [CRITICAL] CVE-2018-20020 libvncserver: Heap out-of-bound write inside structure in VNC client code allows for potential code execution
CVE-2018-20020 libvncserver: Heap out-of-bound write inside structure in VNC client code allows for potential code execution
LibVNC before commit 7b1ef0ffc4815cab9a96c7278394152bdc89dc4d contains heap out-of-bound write vulnerability inside structure in VNC client code that can result remote code execution.
External Reference:
https://ics-cert.kaspersky.com/advisories/klcert-advisories/2018/12/19/klcert-18-030-libvnc-heap-out-of-bound-write/
Upstream Patch:
https://github.com/LibVNC/libvncserver/commit/7b1ef0ffc4815cab9a96c7278394152bdc89dc4d
Discussion:
Created libvncserver tracking bugs for this issue:
Affects: epel-7 [bug 1661119]
Affects: fedora-all [bug 1661118]
---
Upstream Issue:
https://github.com/LibVNC/libvncserver/issues/250
Bugzilla
CVE-2018-20020 libvncserver: Heap out-of-bound write inside structure in VNC client code allows for potential code execution [fedora-all]
bugzilla·2018-12-20·CVSS 9.8
CVE-2018-20020 [CRITICAL] CVE-2018-20020 libvncserver: Heap out-of-bound write inside structure in VNC client code allows for potential code execution [fedora-all]
CVE-2018-20020 libvncserver: Heap out-of-bound write inside structure in VNC client code allows for potential code execution [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 me
https://ics-cert.kaspersky.com/advisories/klcert-advisories/2018/12/19/klcert-18-030-libvnc-heap-out-of-bound-write/https://lists.debian.org/debian-lts-announce/2018/12/msg00017.htmlhttps://lists.debian.org/debian-lts-announce/2019/10/msg00042.htmlhttps://lists.debian.org/debian-lts-announce/2019/11/msg00033.htmlhttps://security.gentoo.org/glsa/201908-05https://security.gentoo.org/glsa/202006-06https://usn.ubuntu.com/3877-1/https://usn.ubuntu.com/4547-1/https://usn.ubuntu.com/4547-2/https://usn.ubuntu.com/4587-1/https://www.debian.org/security/2019/dsa-4383https://ics-cert.kaspersky.com/advisories/klcert-advisories/2018/12/19/klcert-18-030-libvnc-heap-out-of-bound-write/https://lists.debian.org/debian-lts-announce/2018/12/msg00017.htmlhttps://lists.debian.org/debian-lts-announce/2019/10/msg00042.htmlhttps://lists.debian.org/debian-lts-announce/2019/11/msg00033.htmlhttps://security.gentoo.org/glsa/201908-05https://security.gentoo.org/glsa/202006-06https://usn.ubuntu.com/3877-1/https://usn.ubuntu.com/4547-1/https://usn.ubuntu.com/4547-2/https://usn.ubuntu.com/4587-1/https://www.debian.org/security/2019/dsa-4383
2018-12-19
Published