An issue was discovered in LibVNCServer before 0.9.13.
Noroxi assessment
Priority: Monitor (action score 21/100)
- 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: 1.5% (FIRST EPSS); higher than 75.1% of all records.
- Anyone who can reach it over the internet can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
- Fixed version: libvncserver (Debian:12) 0.9.13+dfsg-1; libvncserver (Debian:8) 0.9.9+dfsg2-6.1+deb8u8; libvncserver (Debian:9) 0.9.11+dfsg-1.3~deb9u5.
- Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).
Low priority for now. Upgrade to libvncserver (Debian:12) 0.9.13+dfsg-1; libvncserver (Debian:8) 0.9.9+dfsg2-6.1+deb8u8; libvncserver (Debian:9) 0.9.11+dfsg-1.3~deb9u5 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
An issue was discovered in LibVNCServer before 0.9.13. libvncserver/rre.c allows out-of-bounds access via encodings.
- Published
- Jun 17, 2020
- Updated
- Jun 16, 2026
- EPSS
- 1.6% · 75th percentile
- CWE
- CWE-787
Report tools
Action score
21
Monitor
Low priority for now.
- CVSS
- 21 / 40 · 5.4 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 1.6%
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.
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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 helpAffected 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.
| Vendor | Product | CPE |
|---|---|---|
| libvnc project | libvncserver | cpe:2.3:a:libvnc_project:libvncserver |
| canonical | ubuntu linux | cpe:2.3:o:canonical:ubuntu_linux |
| debian | debian linux | cpe:2.3:o:debian:debian_linux |
| siemens | simatic itc1500 firmware | cpe:2.3:o:siemens:simatic_itc1500_firmware |
| siemens | simatic itc1500 | cpe:2.3:h:siemens:simatic_itc1500 |
| siemens | simatic itc1500 pro firmware | cpe:2.3:o:siemens:simatic_itc1500_pro_firmware |
| siemens | simatic itc1500 pro | cpe:2.3:h:siemens:simatic_itc1500_pro |
| siemens | simatic itc1900 firmware | cpe:2.3:o:siemens:simatic_itc1900_firmware |
| siemens | simatic itc1900 | cpe:2.3:h:siemens:simatic_itc1900 |
| siemens | simatic itc1900 pro firmware | cpe:2.3:o:siemens:simatic_itc1900_pro_firmware |
| siemens | simatic itc1900 pro | cpe:2.3:h:siemens:simatic_itc1900_pro |
| siemens | simatic itc2200 firmware | cpe:2.3:o:siemens:simatic_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
- canonical ubuntu linux20.04
- 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
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| Debian:12 | libvncserver | before 0.9.13+dfsg-1 | 0.9.13+dfsg-1 |
| Debian:8 | libvncserver | before 0.9.9+dfsg2-6.1+deb8u8 | 0.9.9+dfsg2-6.1+deb8u8 |
| Debian:9 | libvncserver | before 0.9.11+dfsg-1.3~deb9u5 | 0.9.11+dfsg-1.3~deb9u5 |
| SUSE:HPE Helion OpenStack 8 | LibVNCServer | before 0.9.9-17.31.1 | 0.9.9-17.31.1 |
Same product
libvnc project: all recordsOther 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 transfer44Plan
- CVE-2018-15126LibVNC before commit 73cb96fec028a576a5a24417b57723b55854ad7b contains heap use-after-free vulnerability in server code of file transfer ext43Plan
- CVE-2018-20020LibVNC before commit 7b1ef0ffc4815cab9a96c7278394152bdc89dc4d contains heap out-of-bound write vulnerability inside structure in VNC client 42Plan
- CVE-2018-20019LibVNC before commit a83439b9fbe0f03c48eb94ed05729cb016f8b72f contains multiple heap out-of-bound write vulnerabilities in VNC client code t42Plan
- CVE-2019-20788libvncclient/cursor.c in LibVNCServer through 0.9.12 has a HandleCursorShape integer overflow and heap-based buffer overflow via a large hei40Plan
- CVE-2018-20750LibVNC through 0.9.12 contains a heap out-of-bounds write vulnerability in libvncserver/rfbserver.c.40Plan
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| debian:libvncserver | 0.9.13+dfsg-1 · Debian:12 | Package registry (OSV) |
| suse:LibVNCServer | 0.9.9-17.31.1 · SUSE:HPE Helion OpenStack 8 | Package 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.
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.
Credits
All researchersFinders, 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).
National notice (Türkiye Cybersecurity Directorate / USOM)
Official security notices citing this record; remediation advice is on the agency's page.
- TR-20-518 · Jul 13, 2020(LibVNCServer Güvenlik Güncellemesi)
Technical details
Attack conditions
- Anyone who can reach it over the internet can trigger it.
- A low-privileged account is enough.
- No user action is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- low · data can be read
- Integrity
- none
- Availability
- low · the service can be disrupted
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- Low
- Integrity impact
- None
- Availability impact
- Low
Weakness class (CWE)
CWE-787 · Out-of-bounds WriteCVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:L
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
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
Show all references (6 more)Show less
- github.com/LibVNC/libvncserver/commit/74e8a70f2c9a5248d6718ce443e07c7ed314dfff
- github.com/LibVNC/libvncserver/compare/LibVNCServer-0.9.12...LibVNCServer-0.9.13
- lists.debian.org/debian-lts-announce/2020/06/msg00035.html
- lists.debian.org/debian-lts-announce/2020/08/msg00045.html
- usn.ubuntu.com/4434-1/
- usn.ubuntu.com/4573-1/
Vendor advisories and official records. Exploit/PoC links are deliberately left out.