CVE-2026-59844 PUBLISHED

Libssh: libssh: denial of service via oversized sftp read length

Assigner: redhat
Reserved: 07.07.2026 Published: 21.07.2026 Updated: 21.07.2026

A flaw was found in libssh. A remote authenticated client can issue SSH_FXP_READ requests with an arbitrarily large length, causing a libssh SFTP server to allocate excessive memory and potentially exhaust it through repeated requests.

Metrics

CVSS 3.1

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
CVSS Score: 6.5

Attack Vector	Network	Scope	Unchanged
Attack Complexity	Low	Confidentiality Impact	None
Privileges Required	Low	Integrity Impact	None
User Interaction	None	Availability Impact	High

CVSS 3.1

Product Status

Vendor	Red Hat
Product	Red Hat Enterprise Linux 10
Versions	Default: affected

Vendor	Red Hat
Product	Red Hat Enterprise Linux 8
Versions	Default: affected

Vendor	Red Hat
Product	Red Hat Enterprise Linux 9
Versions	Default: affected

Vendor	Red Hat
Product	Red Hat Hardened Images
Versions	Default: affected

Workarounds

No workaround available.

Credits

Red Hat would like to thank Chanho Kim for reporting this issue.

References

Problem Types

Memory Allocation with Excessive Size Value CWE