CVE-2018-20021
published 2018-12-19CVE-2018-20021: LibVNC before commit c3115350eb8bb635d0fdb4dbbb0d0541f38ed19c contains a CWE-835: Infinite loop vulnerability in VNC client code. Vulnerability allows attacker…
PriorityP340high7.5CVSS 3.0
AVNACLPRNUINSUCNINAH
EPSS
3.52%
87.8th percentile
LibVNC before commit c3115350eb8bb635d0fdb4dbbb0d0541f38ed19c contains a CWE-835: Infinite loop vulnerability in VNC client code. Vulnerability allows attacker to consume excessive amount of resources like CPU and RAM
Affected
19 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 | tightvnc | < 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 |
| tightvnc | tightvnc | >= 0 < 1:1.3.9-9.1 | 1:1.3.9-9.1 |
| tightvnc | tightvnc | >= 0 < 1:1.3.9-9.1 | 1:1.3.9-9.1 |
| tightvnc | tightvnc | >= 0 < 1:1.3.9-9.1 | 1:1.3.9-9.1 |
| tightvnc | tightvnc | >= 0 < 1:1.3.9-9.1 | 1:1.3.9-9.1 |
CVSS provenance
nvdv3.07.5HIGHCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
nvdv2.07.8HIGHAV:N/AC:L/Au:N/C:N/I:N/A:C
osv9.8CRITICAL
vendor_ubuntu9.8CRITICAL
vendor_debian7.5HIGH
vendor_redhat7.5HIGH
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GHSA
GHSA-m4r6-9jrx-9hxw: LibVNC before commit c3115350eb8bb635d0fdb4dbbb0d0541f38ed19c contains a CWE-835: Infinite loop vulnerability in VNC client code
ghsa_unreviewed·2022-05-13
CVE-2018-20021 [HIGH] CWE-835 GHSA-m4r6-9jrx-9hxw: LibVNC before commit c3115350eb8bb635d0fdb4dbbb0d0541f38ed19c contains a CWE-835: Infinite loop vulnerability in VNC client code
LibVNC before commit c3115350eb8bb635d0fdb4dbbb0d0541f38ed19c contains a CWE-835: Infinite loop vulnerability in VNC client code. Vulnerability allows attacker to consume excessive amount of resources like CPU and RAM
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-2018-20021: LibVNC before commit c3115350eb8bb635d0fdb4dbbb0d0541f38ed19c contains a CWE-835: Infinite loop vulnerability in VNC client code
osv·2018-12-19·CVSS 7.5
CVE-2018-20021 [HIGH] CVE-2018-20021: LibVNC before commit c3115350eb8bb635d0fdb4dbbb0d0541f38ed19c contains a CWE-835: Infinite loop vulnerability in VNC client code
LibVNC before commit c3115350eb8bb635d0fdb4dbbb0d0541f38ed19c contains a CWE-835: Infinite loop vulnerability in VNC client code. Vulnerability allows attacker to consume excessive amount of resources like CPU and RAM
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: Infinite loop in VNC client code allows for denial of service
vendor_redhat·2018-12-19·CVSS 7.5
CVE-2018-20021 [HIGH] CWE-400 libvncserver: Infinite loop in VNC client code allows for denial of service
libvncserver: Infinite loop in VNC client code allows for denial of service
LibVNC before commit c3115350eb8bb635d0fdb4dbbb0d0541f38ed19c contains a CWE-835: Infinite loop vulnerability in VNC client code. Vulnerability allows attacker to consume excessive amount of resources like CPU and RAM
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) - Will not fix
Debian
CVE-2018-20021: libvncserver - LibVNC before commit c3115350eb8bb635d0fdb4dbbb0d0541f38ed19c contains a CWE-835...
vendor_debian·2018·CVSS 7.5
CVE-2018-20021 [HIGH] CVE-2018-20021: libvncserver - LibVNC before commit c3115350eb8bb635d0fdb4dbbb0d0541f38ed19c contains a CWE-835...
LibVNC before commit c3115350eb8bb635d0fdb4dbbb0d0541f38ed19c contains a CWE-835: Infinite loop vulnerability in VNC client code. Vulnerability allows attacker to consume excessive amount of resources like CPU and RAM
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-2018-20021 libvncserver: Infinite loop in VNC client code allows for denial of service [fedora-all]
bugzilla·2018-12-20·CVSS 7.5
CVE-2018-20021 [HIGH] CVE-2018-20021 libvncserver: Infinite loop in VNC client code allows for denial of service [fedora-all]
CVE-2018-20021 libvncserver: Infinite loop in VNC client code allows for denial of service [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 m
Bugzilla
CVE-2018-20021 libvncserver: Infinite loop in VNC client code allows for denial of service [epel-7]
bugzilla·2018-12-20·CVSS 7.5
CVE-2018-20021 [HIGH] CVE-2018-20021 libvncserver: Infinite loop in VNC client code allows for denial of service [epel-7]
CVE-2018-20021 libvncserver: Infinite loop in VNC client code allows for denial of service [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 tem
Bugzilla
CVE-2018-20021 libvncserver: Infinite loop in VNC client code allows for denial of service
bugzilla·2018-12-20·CVSS 7.5
CVE-2018-20021 [HIGH] CVE-2018-20021 libvncserver: Infinite loop in VNC client code allows for denial of service
CVE-2018-20021 libvncserver: Infinite loop in VNC client code allows for denial of service
LibVNC before commit c3115350eb8bb635d0fdb4dbbb0d0541f38ed19c contains a CWE-835: Infinite loop vulnerability in VNC client code. Vulnerability allows attacker to consume excessive amount of resources like CPU and RAM
External Reference:
https://ics-cert.kaspersky.com/advisories/klcert-advisories/2018/12/19/klcert-18-031-libvnc-infinite-loop/
Upstream Patch:
https://github.com/LibVNC/libvncserver/commit/c3115350eb8bb635d0fdb4dbbb0d0541f38ed19c
Discussion:
Created libvncserver tracking bugs for this issue:
Affects: epel-7 [bug 1661122]
Affects: fedora-all [bug 1661121]
---
Upstream Issue:
https://github.com/LibVNC/libvncserver/issues/251
---
I suspect that this was introduced by https:/
https://ics-cert.kaspersky.com/advisories/klcert-advisories/2018/12/19/klcert-18-031-libvnc-infinite-loop/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://lists.debian.org/debian-lts-announce/2019/12/msg00028.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-18-031-libvnc-infinite-loop/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://lists.debian.org/debian-lts-announce/2019/12/msg00028.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