LibVNCServer up to 0.9.11 rfbserver.c rfbProcessClientNormalMessage integer overflow

CVSS Meta Temp Score
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CTI Interest Score
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8.4$0-$5k0.00

Summaryinfo

A vulnerability classified as critical was found in LibVNCServer up to 0.9.11. Affected is the function rfbProcessClientNormalMessage of the file rfbserver.c. Executing a manipulation as part of Message can lead to integer overflow. This vulnerability is handled as CVE-2018-7225. The attack can be executed remotely. There is not any exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in LibVNCServer up to 0.9.11. It has been declared as critical. This vulnerability affects the function rfbProcessClientNormalMessage of the file rfbserver.c. The manipulation as part of a Message leads to a integer overflow vulnerability. The CWE definition for the vulnerability is CWE-190. The product performs a calculation that can produce an integer overflow or wraparound, when the logic assumes that the resulting value will always be larger than the original value. This can introduce other weaknesses when the calculation is used for resource management or execution control. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

An issue was discovered in LibVNCServer through 0.9.11. rfbProcessClientNormalMessage() in rfbserver.c does not sanitize msg.cct.length, leading to access to uninitialized and potentially sensitive data or possibly unspecified other impact (e.g., an integer overflow) via specially crafted VNC packets.

The bug was discovered 02/19/2018. The weakness was released 02/19/2018 by Solar Designer (Website). The advisory is shared for download at openwall.com. This vulnerability was named CVE-2018-7225 since 02/19/2018. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. There are known technical details, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 108669 (Fedora 27 : libvncserver (2018-4897772a43)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Fedora Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 170971 (SUSE Enterprise Linux Security Update for LibVNCServer (SUSE-SU-2018:0830-1)).

Upgrading eliminates this vulnerability. A possible mitigation has been published 2 months after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Tenable (108669) and SecurityFocus (BID 103107†). Once again VulDB remains the best source for vulnerability data.

Productinfo

Name

Version

License

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

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

NVD Base Score: 🔍

Exploitinginfo

Class: Integer overflow
CWE: CWE-190 / CWE-189
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 108669
Nessus Name: Fedora 27 : libvncserver (2018-4897772a43)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 866387
OpenVAS Name: SuSE Update for LibVNCServer openSUSE-SU-2018:0851-1 (LibVNCServer)
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
Exposure Time: 🔍

Timelineinfo

02/18/2018 🔍
02/19/2018 +1 days 🔍
02/19/2018 +0 days 🔍
02/19/2018 +0 days 🔍
02/19/2018 +0 days 🔍
02/20/2018 +1 days 🔍
03/27/2018 +35 days 🔍
03/28/2018 +1 days 🔍
02/08/2023 +1778 days 🔍

Sourcesinfo

Advisory: FEDORA-2018-4897772a43
Researcher: Solar Designer
Status: Not defined

CVE: CVE-2018-7225 (🔍)
GCVE (CVE): GCVE-0-2018-7225
GCVE (VulDB): GCVE-100-113596

OVAL: 🔍

SecurityFocus: 103107 - libVNCserver 'rfbserver.c' Integer Overflow Vulnerability

Entryinfo

Created: 02/20/2018 09:40
Updated: 02/08/2023 14:25
Changes: 02/20/2018 09:40 (74), 01/07/2020 08:35 (6), 02/08/2023 14:20 (4), 02/08/2023 14:25 (1)
Complete: 🔍
Cache ID: 216::103

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