LibVNC File Transfer Extension use after free

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

A vulnerability was found in LibVNC (the affected version unknown). It has been classified as critical. This affects an unknown part 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. The summary by CVE is:

LibVNC before commit 73cb96fec028a576a5a24417b57723b55854ad7b 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 presented 12/19/2018 by Solar Designer (Website). It is possible to read the advisory at ics-cert.kaspersky.com. This vulnerability is uniquely identified as CVE-2018-15126 since 08/06/2018. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. The technical details are unknown and an exploit is not publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 121517 (Debian DLA-1652-1 : 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 73cb96fec028a576a5a24417b57723b55854ad7b is able to eliminate this problem. A possible mitigation has been published 2 months after the disclosure of the vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (121517). See 128104, 128119, 128120 and 128121 for similar entries.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

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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: 🔍
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NVD Base Score: 9.8
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CVSSv2info

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Exploitinginfo

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

Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

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Nessus ID: 121517
Nessus Name: Debian DLA-1652-1 : libvncserver security update
Nessus File: 🔍
Nessus Risk: 🔍
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Threat Intelligenceinfo

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Countermeasuresinfo

Recommended: Patch
Status: 🔍

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0-Day Time: 🔍
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Patch: 73cb96fec028a576a5a24417b57723b55854ad7b

Timelineinfo

08/06/2018 🔍
12/19/2018 +135 days 🔍
12/19/2018 +0 days 🔍
12/19/2018 +0 days 🔍
12/20/2018 +1 days 🔍
01/31/2019 +42 days 🔍
01/31/2019 +0 days 🔍
02/01/2019 +1 days 🔍
06/19/2023 +1599 days 🔍

Sourcesinfo

Advisory: DLA 1617-1
Researcher: Solar Designer
Status: Confirmed

CVE: CVE-2018-15126 (🔍)
SecurityFocus: 106825 - LibVNCServer Incomplete Fix Multiple Heap Buffer Overflow Vulnerabilities

See also: 🔍

Entryinfo

Created: 12/20/2018 07:41
Updated: 06/19/2023 20:06
Changes: 12/20/2018 07:41 (72), 04/21/2020 21:09 (5), 06/19/2023 19:58 (4), 06/19/2023 20:06 (1)
Complete: 🔍

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