UltraVNC Revision 1199 Client CoRRE Decoder out-of-bounds

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.
8.4	$0-$5k	0.00

Summaryinfo

A vulnerability marked as critical has been reported in UltraVNC Revision 1199. This affects an unknown function of the component Client CoRRE Decoder. This manipulation causes out-of-bounds. The identification of this vulnerability is CVE-2019-8261. It is possible to initiate the attack remotely. There is no exploit available. It is recommended to apply a patch to fix this issue.

Detailsinfo

A vulnerability has been found in UltraVNC Revision 1199 (Connectivity Software) and classified as critical. Affected by this vulnerability is an unknown code of the component Client CoRRE Decoder. The manipulation with an unknown input leads to a out-of-bounds vulnerability. The CWE definition for the vulnerability is CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

UltraVNC revision 1199 has a out-of-bounds read vulnerability in VNC code inside client CoRRE decoder, caused by multiplication overflow. This attack appears to be exploitable via network connectivity. This vulnerability has been fixed in revision 1200.

The bug was discovered 03/01/2019. The weakness was shared 03/05/2019. This vulnerability is known as CVE-2019-8261 since 02/12/2019. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. The technical details are unknown and an exploit is not 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 1200 is able to eliminate this problem.

The entries VDB-131316, VDB-131356, VDB-131357 and VDB-131358 are related to this item. Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Type

Connectivity Software

Name

UltraVNC

Version

Revision 1199

License

open-source

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.5
VulDB Meta Temp Score: 8.4

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

NVD Base Score: 9.8
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: Out-of-bounds
CWE: CWE-125 / 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 1200

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-2019-8261 (🔍)
GCVE (CVE): GCVE-0-2019-8261
GCVE (VulDB): GCVE-100-131359
See also: 🔍

Entryinfo

Created: 03/06/2019 08:44
Updated: 07/26/2023 16:29
Changes: 03/06/2019 08:44 (59), 05/28/2020 17:13 (1), 07/26/2023 16:29 (5)
Complete: 🔍
Cache ID: 216::103