Skip to content
Noroxi
CVE-2018-20019· NVD / CVE Program· CNA Kaspersky

LibVNC before commit a83439b9fbe0f03c48eb94ed05729cb016f8b72f contains multiple heap out-of-bound write vulnerabilities in VNC client code t

Noroxi assessment

Priority: Plan (action score 42/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 9.4% (FIRST EPSS); higher than 95.3% of all records.
  • Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
  • Fixed version: libvncserver (Debian:12) 0.9.11+dfsg-1.2; italc (Debian:8) 1:2.0.2+dfsg1-2+deb8u1; libvncserver (Debian:8) 0.9.9+dfsg2-6.1+deb8u4.

Add it to your regular patch cycle. Upgrade to libvncserver (Debian:12) 0.9.11+dfsg-1.2; italc (Debian:8) 1:2.0.2+dfsg1-2+deb8u1; libvncserver (Debian:8) 0.9.9+dfsg2-6.1+deb8u4 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

LibVNC before commit a83439b9fbe0f03c48eb94ed05729cb016f8b72f contains multiple heap out-of-bound write vulnerabilities in VNC client code that can result remote code execution

CriticalCVSS 9.8 · v3.1—No exploit Fix available
Published
Dec 19, 2018
Updated
Jun 16, 2026
EPSS
9.4% · 95th percentile

Report tools

JSON

Action score

42

Plan

Add it to your regular patch cycle.

CVSS
39 / 40 · 9.8 / 10
CISA KEV
0 / 30 · Not listed
EPSS
3 / 30 · 9.4%

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

If any of these changes, we'll tell you in the daily email digest.

Follow CVE-2018-20019

When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

One daily email digest (06:00 UTC); connect a webhook for KEV listings and weaponized exploits instantly.

Your free account also gets you

Running WordPress? Scan your site free with WP Lens

  • Stack alerts: add the products and versions you run, get the new CVEs that affect them
  • Uptime monitoring: 1 site, instant email when it goes down
  • Add your domain: subdomains and takeover risk scanned every week (1 domain)
  • 10 scans an hour on the security tools (3 a day without an account), an API key and MCP
  • All your scans in one panel: findings, what changed in the last scan, a report per domain or per client (PDF, share link)
All free tools

Sign up with email · Have an account? Sign in

Free account, no card. Unfollow any time.

Don't want an account? Get "Exploited this week" by email every MondayDon't want an account? RSS feed for libvnc project records

Running WordPress? Scan your site free with WP Lens

Is your version affected? Check it

Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

We use this product, ask for help

Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
libvnc projectlibvncserver
canonicalubuntu linux
debiandebian linux
siemenssimatic itc1500 firmware
siemenssimatic itc1500
siemenssimatic itc1500 pro firmware
siemenssimatic itc1500 pro
siemenssimatic itc1900 firmware
siemenssimatic itc1900
siemenssimatic itc1900 pro firmware
siemenssimatic itc1900 pro
siemenssimatic itc2200 firmware

and 3 more

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • canonical ubuntu linux14.04
  • canonical ubuntu linux16.04
  • canonical ubuntu linux18.04
  • canonical ubuntu linux18.10
  • debian debian linux8.0
  • debian debian linux9.0
  • libvnc project libvncserverbefore 0.9.12
  • siemens simatic itc1500 firmware3.0.0.0 and later · before 3.2.1.0
  • siemens simatic itc1500 pro firmware3.0.0.0 and later · before 3.2.1.0
  • siemens simatic itc1900 firmware3.0.0.0 and later · before 3.2.1.0
  • siemens simatic itc1900 pro firmware3.0.0.0 and later · before 3.2.1.0
  • siemens simatic itc2200 firmware3.0.0.0 and later · before 3.2.1.0
  • siemens simatic itc2200 pro firmware3.0.0.0 and later · before 3.2.1.0

Versions reported by the vendor

Affected version ranges reported by the assigning authority (Kaspersky). Independent of NVD's CPE analysis and usually ahead of it.

  • n/a LibVNC

    • commit a83439b9fbe0f03c48eb94ed05729cb016f8b72faffected

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
Debian:12libvncserverbefore 0.9.11+dfsg-1.20.9.11+dfsg-1.2
Debian:8italcbefore 1:2.0.2+dfsg1-2+deb8u11:2.0.2+dfsg1-2+deb8u1
Debian:8libvncserverbefore 0.9.9+dfsg2-6.1+deb8u40.9.9+dfsg2-6.1+deb8u4
Debian:9libvncserverbefore 0.9.11+dfsg-1.3~deb9u10.9.11+dfsg-1.3~deb9u1
openSUSE:Leap 15.0LibVNCServerbefore 0.9.10-lp150.3.3.10.9.10-lp150.3.3.1
SUSE:Linux Enterprise Module for Package Hub 15LibVNCServerbefore 0.9.10-4.3.10.9.10-4.3.1
SUSE:Linux Enterprise Software Development Kit 11 SP4LibVNCServerbefore 0.9.1-160.6.10.9.1-160.6.1
SUSE:OpenStack Cloud 7LibVNCServerbefore 0.9.9-17.8.10.9.9-17.8.1

Same product

libvnc project: all records

Other highest-scoring records for the same primary product.

  • CVE-2018-15127LibVNC before commit 502821828ed00b4a2c4bef90683d0fd88ce495de contains heap out-of-bound write vulnerability in server code of file transfer
    44Plan
  • CVE-2018-15126LibVNC before commit 73cb96fec028a576a5a24417b57723b55854ad7b contains heap use-after-free vulnerability in server code of file transfer ext
    43Plan
  • CVE-2018-20020LibVNC before commit 7b1ef0ffc4815cab9a96c7278394152bdc89dc4d contains heap out-of-bound write vulnerability inside structure in VNC client
    42Plan

Published before and after this one in the same product

  • Later →CVE-2018-20021Dec 19, 2018 · LibVNC before commit c3115350eb8bb635d0fdb4dbbb0d0541f38ed19c contains a CWE-835: Infinite loop vulnerability in VNC client code.
    31Monitor
  • Later →CVE-2018-20022Dec 19, 2018 · LibVNC before 2f5b2ad1c6c99b1ac6482c95844a84d66bb52838 contains multiple weaknesses CWE-665: Improper Initialization vulnerability in VNC cl
    31Monitor
  • Later →CVE-2018-20023Dec 19, 2018 · LibVNC before 8b06f835e259652b0ff026898014fc7297ade858 contains CWE-665: Improper Initialization vulnerability in VNC Repeater client code t
    31Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
debian:italc1:2.0.2+dfsg1-2+deb8u1 · Debian:8Package registry (OSV)
debian:libvncserver0.9.11+dfsg-1.2 · Debian:12Package registry (OSV)
opensuse:LibVNCServer0.9.10-lp150.3.3.1 · openSUSE:Leap 15.0Package registry (OSV)
suse:LibVNCServer0.9.9-17.8.1 · SUSE:OpenStack Cloud 7Package registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • No account or password is required.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
high · data can be read
Integrity
high · data or configuration can be modified
Availability
high · the service can be disrupted
Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality impact
High
Integrity impact
High
Availability impact
High

Weakness class (CWE)

CWE-787 · Out-of-bounds Write

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

nvd-primary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

MITRE has no CAPEC/ATT&CK mapping for this CWE.

Change log

  1. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

Show all references (8 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records