LibVNC File Transfer Extension use after free

CVSS Meta Temp Score
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CTI Interest Score
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7.5$0-$5k0.00

A vulnerability, which was classified as critical, was found in LibVNC (affected version unknown). Affected is an unknown functionality of the component File Transfer Extension. The manipulation with an unknown input leads to a use after free vulnerability. CWE is classifying the issue as CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

LibVNC before commit ca2a5ac02fbbadd0a21fabba779c1ea69173d10b contains heap use-after-free vulnerability in server code of file transfer extension that can result remote code execution.

The bug was discovered 12/19/2018. The weakness was released 12/19/2018 by Solar Designer (Website). The advisory is shared for download at ics-cert.kaspersky.com. This vulnerability is traded as CVE-2018-6307 since 01/25/2018. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. There are neither technical details nor an exploit publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 119877 (Debian DLA-1617-1 : libvncserver security update), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Debian Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 171837 (SUSE Enterprise Linux Security Update for LibVNCServer (SUSE-SU-2019:0060-1)).

Applying the patch ca2a5ac02fbbadd0a21fabba779c1ea69173d10b is able to eliminate this problem. A possible mitigation has been published 1 weeks after the disclosure of the vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (119877). Entries connected to this vulnerability are available at 128103, 128104, 128119 and 128120.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB CVSS-B Score: 🔍
VulDB CVSS-BT Score: 🔍
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CVSSv3info

VulDB Meta Base Score: 7.7
VulDB Meta Temp Score: 7.5

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

NVD Base Score: 8.1
NVD Vector: 🔍

CVSSv2info

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VulDB Base Score: 🔍
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Exploitinginfo

Class: Use after free
CWE: CWE-416 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

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EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 119877
Nessus Name: Debian DLA-1617-1 : libvncserver security update
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

Interest: 🔍
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Countermeasuresinfo

Recommended: Patch
Status: 🔍

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

Patch: ca2a5ac02fbbadd0a21fabba779c1ea69173d10b

Timelineinfo

01/25/2018 🔍
12/19/2018 +328 days 🔍
12/19/2018 +0 days 🔍
12/19/2018 +0 days 🔍
12/20/2018 +1 days 🔍
12/26/2018 +6 days 🔍
12/27/2018 +1 days 🔍
01/31/2019 +35 days 🔍
06/20/2023 +1601 days 🔍

Sourcesinfo

Advisory: 241
Researcher: Solar Designer
Status: Confirmed

CVE: CVE-2018-6307 (🔍)
SecurityFocus: 106825 - LibVNCServer Incomplete Fix Multiple Heap Buffer Overflow Vulnerabilities

See also: 🔍

Entryinfo

Created: 12/20/2018 07:55
Updated: 06/20/2023 07:31
Changes: 12/20/2018 07:55 (72), 04/22/2020 09:33 (5), 06/20/2023 07:26 (4), 06/20/2023 07:31 (1)
Complete: 🔍

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