← Vulnerability feed

Vulnerability record · CVE-2026-59842 · published 21 July 2026

CVE-2026-59842: Libssh out-of-bounds read vulnerability

Libssh · Libssh

A flaw was found in libssh. During server-side GSSAPI key exchange, a client-supplied Curve25519 public key shorter than the expected length is copied without proper length validation, leading to an out-of-bounds heap read. This could allow a remote unauthenticated attacker to disclose small amounts of server memory.

5.3 CVSS 3.1 Medium EPSS 0.49% · top 60.1% CWE-125 · Out-of-bounds read
5.3CVSS 3.1 base score
0.49%EPSS exploitation probability, 30 days
NoNot in CISA KEV
11Affected product versions listed by NVD
4References
22 Sep 2026Last modified by NVD

Description

A flaw was found in libssh. During server-side GSSAPI key exchange, a client-supplied Curve25519 public key shorter than the expected length is copied without proper length validation, leading to an out-of-bounds heap read. This could allow a remote unauthenticated attacker to disclose small amounts of server memory.

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

Affected products

11 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://access.redhat.com/errata/RHSA-2026:42922 Issue Tracking
https://access.redhat.com/errata/RHSA-2026:55855 Vendor Advisory
https://access.redhat.com/security/cve/CVE-2026-59842 Vendor Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2498168 Issue TrackingVendor Advisory

Track CVE-2026-59842 inside VULONE

Watch it alongside the ransomware crews, C2 infrastructure and forum chatter that reference it, query it through the API and pull it into your SIEM over TAXII.

Start free Open in platform

Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

9.8CVE-2019-5544OpenSLP heap out-of-bounds write in VMware ESXi and Horizon DaaSOpenSLP as shipped in VMware ESXi and Horizon DaaS contains a heap overwrite (out-of-bounds write) flaw. VMware rates it Critical with a maximum CVSS…KEVEPSS 97%analysed9.8CVE-2019-11043PHP-FPM buffer overflow enables remote code executionPHP-FPM in certain configurations writes past allocated buffers into FCGI protocol data space, an out-of-bounds write (CWE-787, CWE-120). It affects …KEVEPSS 100%analysed9.8CVE-2018-14667RichFaces Framework EL injection enables unauthenticated remote code executionRichFaces Framework 3.X through 3.3.4 is vulnerable to Expression Language injection through the UserResource resource. A remote, unauthenticated att…KEVEPSS 74%analysed9.8CVE-2015-2590Oracle Java SE Libraries flaw allows remote code executionCVE-2015-2590 is an unspecified vulnerability in the Libraries component of Oracle Java SE 6u95, 7u80, 8u45 and Java SE Embedded 7u75, 8u33. The reco…KEVEPSS 25%analysed9.8CVE-2014-7169GNU Bash environment variable function parsing command injection (Shellshock variant)GNU Bash through 4.3 bash43-025 processes trailing strings after malformed function definitions in environment variable values, allowing command inje…KEVEPSS 100%analysed9.8CVE-2014-6271GNU Bash environment variable command injection (ShellShock)GNU Bash through 4.3 processes trailing strings after function definitions in environment variable values, allowing injected commands to run when Bas…KEVEPSS 100%analysed9.0CVE-2021-40438Apache HTTP Server mod_proxy SSRF via crafted URI pathA crafted request URI path can make mod_proxy forward the request to an origin server chosen by the remote user, an SSRF flaw in Apache HTTP Server 2…KEVEPSS 100%analysed8.8CVE-2025-31277Apple WebKit memory corruption via malicious web contentApple WebKit fails to handle memory correctly when processing crafted web content, leading to memory corruption across Safari, iOS, iPadOS, macOS, tv…KEVEPSS 1.6%analysed

Source: NIST National Vulnerability Database (record CVE-2026-59842), CISA KEV, FIRST EPSS (scores of 2026-09-27). This page is refreshed as NVD updates the record.