libssh2 up to 1.11.1 src/userauth.c userauth_password username_len/password_len integer overflow

CVSS Meta Temp Score
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CTI Interest Score
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7.1$0-$5k0.00

Summaryinfo

A vulnerability classified as critical has been found in libssh2 up to 1.11.1. This affects the function userauth_password of the file src/userauth.c. Performing a manipulation of the argument username_len/password_len results in integer overflow. This vulnerability is known as CVE-2026-7598. Remote exploitation of the attack is possible. No exploit is available. To fix this issue, it is recommended to deploy a patch.

Detailsinfo

A vulnerability was found in libssh2 up to 1.11.1. It has been classified as critical. This affects the function userauth_password of the file src/userauth.c. The manipulation of the argument username_len/password_len 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.

It is possible to read the advisory at github.com. This vulnerability is uniquely identified as CVE-2026-7598. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Technical details of the vulnerability are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 311788 (Linux Distros Unpatched Vulnerability : CVE-2026-7598), which helps to determine the existence of the flaw in a target environment.

Applying the patch 256d04b60d80bf1190e96b0ad1e91b2174d744b1 is able to eliminate this problem. The bugfix is ready for download at github.com.

The vulnerability is also documented in the databases at Tenable (311788) and EUVD (EUVD-2026-26722). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

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Version

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Website

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: 7.3
VulDB Meta Temp Score: 7.1

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

CNA Base Score: 7.3
CNA Vector: 🔒

CVSSv2info

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

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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Nessus ID: 311788
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2026-7598

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔒

Patch: 256d04b60d80bf1190e96b0ad1e91b2174d744b1

Timelineinfo

05/01/2026 Advisory disclosed
05/01/2026 +0 days VulDB entry created
07/02/2026 +62 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: 1858
Status: Confirmed

CVE: CVE-2026-7598 (🔒)
GCVE (CVE): GCVE-0-2026-7598
GCVE (VulDB): GCVE-100-360555
EUVD: 🔒

Entryinfo

Created: 05/01/2026 12:50
Updated: 07/02/2026 17:07
Changes: 05/01/2026 12:50 (56), 05/02/2026 06:29 (1), 05/03/2026 17:41 (2), 07/02/2026 17:07 (30)
Complete: 🔍
Submitter: dapickle
Cache ID: 216::103

Submitinfo

Accepted

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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