UltraVNC Revision 1203 Client RAW Decoder memory corruption

HistoryDiffrelatejsonxmlCTI

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
6.8	$0-$5k	0.00

Summaryinfo

A vulnerability classified as critical has been found in UltraVNC Revision 1203. Affected is an unknown function of the component Client RAW Decoder. Performing a manipulation results in memory corruption. This vulnerability is identified as CVE-2019-8263. The attack can be initiated remotely. There is not any exploit available. It is suggested to install a patch to address this issue.

Detailsinfo

A vulnerability was found in UltraVNC Revision 1203 (Connectivity Software). It has been classified as critical. This affects some unknown processing of the component Client RAW Decoder. The manipulation with an unknown input leads to a memory corruption vulnerability. CWE is classifying the issue as CWE-119. The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

UltraVNC revision 1203 has out-of-bounds access vulnerability in VNC client inside RAW decoder, which can potentially result code in execution. This attack appears to be exploitable via network connectivity. This vulnerability has been fixed in revision 1204.

The bug was discovered 03/01/2019. The weakness was released 03/05/2019. This vulnerability is uniquely identified as CVE-2019-8263 since 02/12/2019. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Neither technical details nor an exploit are publicly available.

The vulnerability was handled as a non-public zero-day exploit for at least 4 days. During that time the estimated underground price was around $0-$5k. The commercial vulnerability scanner Qualys is able to test this issue with plugin 371706 (UltraVNC Multiple Code Execution Vulnerabilities).

Applying the patch Revision 1204 is able to eliminate this problem.

Entries connected to this vulnerability are available at VDB-131316, VDB-131356, VDB-131357 and VDB-131358. Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Type

Connectivity Software

Name

UltraVNC

Version

Revision 1203

License

open-source

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.9
VulDB Meta Temp Score: 6.8

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 6.5
NVD Vector: 🔍

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock

VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Memory corruption
CWE: CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔍

Patch: Revision 1204

Timelineinfo

02/12/2019 🔍
03/01/2019 +17 days 🔍
03/05/2019 +4 days 🔍
03/06/2019 +1 days 🔍
07/26/2023 +1603 days 🔍

Sourcesinfo

Advisory: ssa-286838
Status: Not defined

CVE: CVE-2019-8263 (🔍)
GCVE (CVE): GCVE-0-2019-8263
GCVE (VulDB): GCVE-100-131361
See also: 🔍

Entryinfo

Created: 03/06/2019 08:46
Updated: 07/26/2023 16:51
Changes: 03/06/2019 08:46 (59), 05/28/2020 17:28 (1), 07/26/2023 16:44 (5), 07/26/2023 16:51 (1)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.