Vulnerability · Published Jul 21, 2026 · Assigned by redhat
CVE-2026-59842Libssh: libssh: information disclosure via short gssapi curve25519 public key
Low 3.7
In plain English
A low-severity out-of-bounds read in Red Hat Enterprise Linux 10 from Red Hat. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 43% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official 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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux:10 | libssh | 0.12.0-3.el10_2 | ALSA-2026:55855 |
| AlmaLinux:10 | libssh-config | 0.12.0-3.el10_2 | ALSA-2026:55855 |
| AlmaLinux:10 | libssh-devel | 0.12.0-3.el10_2 | ALSA-2026:55855 |
| Alpine:v3.24 | libssh | 0.12.1-r0 | ALPINE-CVE-2026-59842 |
| Debian:14 | libssh | 0.12.1-1 | DEBIAN-CVE-2026-59842 |
| Rocky Linux:10 | libssh | 0:0.12.0-3.el10_2 | RLSA-2026:55855 |
| Ubuntu:22.04:LTS | libssh | no fix listed | UBUNTU-CVE-2026-59842 |
| Ubuntu:24.04:LTS | libssh | no fix listed | UBUNTU-CVE-2026-59842 |
| Ubuntu:26.04:LTS | libssh | no fix listed | UBUNTU-CVE-2026-59842 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Red Hat | Red Hat Enterprise Linux 10 | see references |
| Red Hat | Red Hat Hardened Images | see references |
| Red Hat | Red Hat Enterprise Linux 8 | see references |
| Red Hat | Red Hat Enterprise Linux 9 | see references |
Weakness: CWE-125 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N
References
- RHSA-2026:42922 vendor-advisory, x_refsource_REDHAT
- RHSA-2026:55855 vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/security/cve/CVE-2026-59842 vdb-entry, x_refsource_REDHAT
- RHBZ#2498168 issue-tracking, x_refsource_REDHAT