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CVE-2026-59849

Libssh: libssh: denial of service via automatic certificate authentication loop

Published: Jul 21, 2026Updated: Jul 30, 2026 Sources: CVE List NVDCWE-835
3.1LOW
NVD MITRE
EPSS Score
0.2%
Top 85.4%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available
Self-Check
OpenVAS

Description

A flaw was found in libssh. Logic errors in automatic certificate-based public key authentication can cause libssh clients to loop indefinitely when configured certificates are missing or repeatedly rejected by a server, leading to denial of service.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:HPR:LUI:NS:UC:NI:NA:L
Exploitability
AV:NAttack Vector
Network
AC:HAttack Complexity
High
PR:LPrivileges Required
Low
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:NConfidentiality
None
I:NIntegrity
None
A:LAvailability
Low
Open in CVSS calculator →

Weaknesses

CWE-835

Affected Products

Red Hat
commercial·USaka redhat
Red Hat Hardened ImagesOn-premOS
Operating Systems / linux-distro
Red Hat Enterprise Linux 10On-premOS
Operating Systems / linux-distro
hardened imagesOn-prem
Operating Systems / linux-distro
libssh
oss-projectaka libssh2 (related, sometimes confused)
libsshLibrary
OSS Libraries / generic-library
and 3 more affected products View all →

Exploitability

Official Patch Available
Workaround Available
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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique
Impact
View detailed technique mapping

References

https://access.redhat.com/errata/RHSA-2026:42922
access.redhat.com
https://access.redhat.com/security/cve/CVE-2026-59849
access.redhat.com
https://bugzilla.redhat.com/show_bug.cgi?id=2498182
bugzilla.redhat.com

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