Bug 2445579 (CVE-2026-3731)

Summary:	CVE-2026-3731 libssh: libssh: Denial of Service via out-of-bounds read in SFTP extension name handler
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security DevOps Team <prodsec-dev>
Status:	NEW ---	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	kshier, rhel-process-autobot, stcannon, teagle, watson-tool-maintainers, yguenane
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
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Doc Text:	A flaw was found in libssh. A remote attacker could trigger an out-of-bounds read vulnerability in the SFTP Extension Name Handler by manipulating the `idx` argument in the `sftp_extensions_get_name` or `sftp_extensions_get_data` functions. This could lead to a Denial of Service (DoS), making the affected system unresponsive.	Story Points:	---
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oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:	2445661, 2445658, 2445659, 2445660
Bug Blocks:

Description OSIDB Bzimport 2026-03-08 11:01:25 UTC

A weakness has been identified in libssh up to 0.11.3. The impacted element is the function sftp_extensions_get_name/sftp_extensions_get_data of the file src/sftp.c of the component SFTP Extension Name Handler. Executing a manipulation of the argument idx can lead to out-of-bounds read. The attack may be performed from remote. Upgrading to version 0.11.4 and 0.12.0 is sufficient to resolve this issue. This patch is called 855a0853ad3abd4a6cd85ce06fce6d8d4c7a0b60. You should upgrade the affected component.