Medium 5.3Published Jul 21, 2026

CVE-2026-59848Libssh: libssh: denial of service via sftp responses with unknown request ids

Updated under an hour ago (Oct 27, 2026, 5:50 AM ET)

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It affects Red Hat Enterprise Linux 10 and 3 other products. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

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Every CVE for Red Hat Enterprise Linux 10

Exploited in the last 30 days

A flaw was found in libssh. A malicious SFTP server can send responses for unknown request IDs that libssh clients keep queued indefinitely, causing unbounded memory growth and client-side denial of service.

CVSS: 5.3 MEDIUM (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Weakness (CWE): CWE-770
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: redhat
NVD analysis: Modified
Record last updated: Sep 1, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

Red Hat Red Hat Enterprise Linux 10 redhat:enterprise_linux	from 0:0.12.0-3.el10_2 not affected	CNA record
Red Hat Red Hat Hardened Images redhat:hummingbird	from 0.12.1-4.hum1 not affected	CNA record
libssh libssh libssh:libssh	all versions	NVD
redhat hardened_images redhat:hardened_images	all versions	NVD
redhat enterprise_linux redhat:enterprise_linux	8.0; 9.0; 10.0	NVD

References

References

https://access.redhat.com/errata/RHSA-2026:42922	vendor-advisory, x-refsource-redhat
https://access.redhat.com/errata/RHSA-2026:55855	vendor-advisory, x-refsource-redhat
https://access.redhat.com/errata/RHSA-2026:62217	vendor-advisory, x-refsource-redhat
https://access.redhat.com/errata/RHSA-2026:62218	vendor-advisory, x-refsource-redhat
https://access.redhat.com/security/cve/CVE-2026-59848	vdb-entry, x-refsource-redhat, vendor-advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2498181	issue-tracking, x-refsource-redhat, vendor-advisory

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.