CVE-2026-59843
Published: July 22, 2026Last modified: July 29, 2026
Description
A flaw was found in libssh. A remote authenticated peer can advertise a zero maximum packet size in SSH_MSG_CHANNEL_OPEN, causing later channel writes to loop indefinitely and consume CPU, leading to denial of service.
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score | 6.5 |
| Attack Vector | NETWORK |
| Attack complexity | LOW |
| Privileges required | LOW |
| User interaction | NONE |
| Scope | UNCHANGED |
| Confidentiality | NONE |
| Integrity impact | NONE |
| Availability impact | HIGH |
| Vector | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
Status
| Product | Release | Package | Status |
|---|---|---|---|
| Alpaquita Linux | 23 LTS | libssh | Fixed (0.11.5-r0) |
| 25 LTS | libssh | Fixed (0.11.5-r0) | |
| Stream | libssh | Fixed (0.12.1-r0) |