Libssh2 up to 1.8.0 SSH Server SFTP Packet out-of-bounds

CVSS Meta Temp Score
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CTI Interest Score
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7.0$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as critical, has been found in Libssh2 up to 1.8.0. The affected element is an unknown function of the component SSH Server. Performing a manipulation as part of SFTP Packet results in out-of-bounds. This vulnerability is known as CVE-2019-3858. Remote exploitation of the attack is possible. No exploit is available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, was found in Libssh2 up to 1.8.0. This affects an unknown functionality of the component SSH Server. The manipulation as part of a SFTP Packet leads to a out-of-bounds vulnerability. CWE is classifying the issue as CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

An out of bounds read flaw was discovered in libssh2 before 1.8.1 when a specially crafted SFTP packet is received from the server. A remote attacker who compromises a SSH server may be able to cause a Denial of Service or read data in the client memory.

The bug was discovered 03/18/2019. The weakness was published 03/21/2019 by Chris Coulson as confirmed bug report (Bugzilla). The advisory is shared at bugzilla.redhat.com. This vulnerability is uniquely identified as CVE-2019-3858 since 01/03/2019. The exploitability is told to be easy. 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 3 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 172157 (SUSE Enterprise Linux Security Update for libssh2_org (SUSE-SU-2019:13982-1)).

Upgrading to version 1.8.1 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at SecurityFocus (BID 107485†). Similar entries are available at VDB-131993, VDB-131994, VDB-132104 and VDB-132210. Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.1
VulDB Meta Temp Score: 7.0

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

NVD Base Score: 9.1
NVD Vector: 🔍

CNA Base Score: 5.0
CNA Vector (Red Hat, Inc.): 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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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: 🔍

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Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Libssh2 1.8.1

Timelineinfo

01/03/2019 🔍
03/18/2019 +74 days 🔍
03/18/2019 +0 days 🔍
03/21/2019 +3 days 🔍
03/23/2019 +2 days 🔍
08/04/2023 +1595 days 🔍

Sourcesinfo

Advisory: RHSA-2019:2136
Researcher: Chris Coulson
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2019-3858 (🔍)
GCVE (CVE): GCVE-0-2019-3858
GCVE (VulDB): GCVE-100-132105
SecurityFocus: 107485 - libssh2 Multiple Security Vulnerabilities

See also: 🔍

Entryinfo

Created: 03/23/2019 09:28
Updated: 08/04/2023 14:30
Changes: 03/23/2019 09:28 (64), 05/19/2020 10:12 (5), 08/04/2023 14:26 (4), 08/04/2023 14:30 (12)
Complete: 🔍
Cache ID: 216:B09:103

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

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