Libssh2 up to 1.8.0 SSH Server integer overflow

CVSS Meta Temp Score
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CTI Interest Score
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7.8$0-$5k0.00

Summaryinfo

A vulnerability categorized as critical has been discovered in Libssh2 up to 1.8.0. Affected by this issue is some unknown functionality of the component SSH Server. The manipulation results in integer overflow. This vulnerability is known as CVE-2019-3856. It is possible to launch the attack remotely. No exploit is available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability classified as critical has been found in Libssh2 up to 1.8.0. Affected is an unknown functionality of the component SSH Server. The manipulation with an unknown input leads to a integer overflow vulnerability. CWE is classifying the issue as 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. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

An integer overflow flaw, which could lead to an out of bounds write, was discovered in libssh2 before 1.8.1 in the way keyboard prompt requests are parsed. A remote attacker who compromises a SSH server may be able to execute code on the client system when a user connects to the server.

The bug was discovered 03/18/2019. The weakness was published 03/25/2019 by Chris Coulson as confirmed bug report (Bugzilla). The advisory is available at bugzilla.redhat.com. This vulnerability is traded as CVE-2019-3856 since 01/03/2019. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. The technical details are unknown and an exploit is not available.

The vulnerability was handled as a non-public zero-day exploit for at least 7 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-132105. If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.9
VulDB Meta Temp Score: 7.8

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

NVD Base Score: 8.8
NVD Vector: 🔍

CNA Base Score: 7.5
CNA Vector (Red Hat, Inc.): 🔍

CVSSv2info

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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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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 🔍
03/25/2019 +7 days 🔍
03/26/2019 +1 days 🔍
08/07/2023 +1595 days 🔍

Sourcesinfo

Advisory: RHSA-2019:0679
Researcher: Chris Coulson
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2019-3856 (🔍)
GCVE (CVE): GCVE-0-2019-3856
GCVE (VulDB): GCVE-100-132210
SecurityFocus: 107485 - libssh2 Multiple Security Vulnerabilities

See also: 🔍

Entryinfo

Created: 03/26/2019 14:02
Updated: 08/07/2023 10:02
Changes: 03/26/2019 14:02 (62), 05/20/2020 06:56 (5), 08/07/2023 10:00 (4), 08/07/2023 10:02 (12)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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