libssh up to 0.11.3 SFTP Extension Name src/sftp.c sftp_extensions_get_name/sftp_extensions_get_data idx out-of-bounds

CVSS Meta Temp Score
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CTI Interest Score
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6.0$0-$5k0.11

Summaryinfo

A vulnerability has been found in libssh up to 0.11.3 and classified as problematic. This affects the function sftp_extensions_get_name/sftp_extensions_get_data of the file src/sftp.c of the component SFTP Extension Name Handler. The manipulation of the argument idx leads to out-of-bounds. This vulnerability is traded as CVE-2026-3731. It is possible to initiate the attack remotely. There is no exploit available. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in libssh up to 0.11.3 and classified as problematic. This issue affects the function sftp_extensions_get_name/sftp_extensions_get_data of the file src/sftp.c of the component SFTP Extension Name Handler. The manipulation of the argument idx with an unknown input leads to a out-of-bounds vulnerability. Using CWE to declare the problem leads to CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. Impacted is availability.

The advisory is shared at libssh.org. The identification of this vulnerability is CVE-2026-3731. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Technical details are known, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 301503 (Linux Distros Unpatched Vulnerability : CVE-2026-3731), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 0.11.4 or 0.12.0 eliminates this vulnerability. The upgrade is hosted for download at libssh.org. Applying the patch 855a0853ad3abd4a6cd85ce06fce6d8d4c7a0b60 is able to eliminate this problem. The bugfix is ready for download at gitlab.com. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (301503) and EUVD (EUVD-2026-10234). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 6.0
VulDB Meta Temp Score: 6.0

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 7.5
NVD Vector: 🔒

CNA Base Score: 5.3
CNA Vector: 🔒

CVSSv2info

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

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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Nessus ID: 301503
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2026-3731

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: libssh 0.11.4/0.12.0
Patch: 855a0853ad3abd4a6cd85ce06fce6d8d4c7a0b60

Timelineinfo

03/07/2026 Advisory disclosed
03/07/2026 +0 days VulDB entry created
03/12/2026 +5 days VulDB entry last update

Sourcesinfo

Advisory: libssh-2026-sftp-extensions
Status: Confirmed

CVE: CVE-2026-3731 (🔒)
GCVE (CVE): GCVE-0-2026-3731
GCVE (VulDB): GCVE-100-349709
EUVD: 🔒

Entryinfo

Created: 03/07/2026 19:00
Updated: 03/12/2026 20:39
Changes: 03/07/2026 19:00 (59), 03/08/2026 15:07 (1), 03/08/2026 18:58 (30), 03/09/2026 15:37 (2), 03/12/2026 20:39 (12)
Complete: 🔍
Cache ID: 216:FE6:103

Submitinfo

Accepted

  • Submit #767120: libssh.org libssh libssh < 0.11.4; < 0.12.0 Out-of-Bounds Read (by libssh.org)

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