Bug 2503673 - CVE-2026-59848 libssh: libssh: denial of service via SFTP responses with unknown request IDs [fedora-all]
Summary: CVE-2026-59848 libssh: libssh: denial of service via SFTP responses with unkn...
Keywords:
Status: CLOSED ERRATA
Alias: None
Product: Fedora
Classification: Fedora
Component: libssh
Version: rawhide
Hardware: Unspecified
OS: Unspecified
medium
medium
Target Milestone: ---
Assignee: Andreas Schneider
QA Contact: Fedora Extras Quality Assurance
URL:
Whiteboard: {"flaws": ["45084a98-a255-4c96-bf32-c...
Depends On:
Blocks: CVE-2026-59848
TreeView+ depends on / blocked
 
Reported: 2026-07-21 15:13 UTC by Vladimir Vasilev
Modified: 2026-07-23 01:20 UTC (History)
5 users (show)

Fixed In Version: libssh-0.11.5-1.fc43 libssh-0.12.1-1.fc44
Clone Of:
Environment:
Last Closed: 2026-07-23 01:03:32 UTC
Type: ---
Embargoed:
fedora-admin-xmlrpc: mirror+


Attachments (Terms of Use)

Description Vladimir Vasilev 2026-07-21 15:13:35 UTC
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.

A flaw was found in libssh client-side SFTP message handling. In sftp_get_message() in src/sftp_common.c, SFTP responses carrying unknown request IDs were accepted and kept queued instead of being rejected. A malicious SFTP server can repeatedly send responses for request IDs that were never issued by the client, causing unbounded growth of queued messages and leading to client-side memory exhaustion and denial of service.

Comment 1 Fedora Update System 2026-07-22 09:32:49 UTC
FEDORA-2026-0e46c91ccf (libssh-0.12.1-1.fc44) has been submitted as an update to Fedora 44.
https://bodhi.fedoraproject.org/updates/FEDORA-2026-0e46c91ccf

Comment 2 Fedora Update System 2026-07-22 09:33:47 UTC
FEDORA-2026-063caa9112 (libssh-0.11.5-1.fc43) has been submitted as an update to Fedora 43.
https://bodhi.fedoraproject.org/updates/FEDORA-2026-063caa9112

Comment 3 Fedora Update System 2026-07-23 01:03:32 UTC
FEDORA-2026-063caa9112 (libssh-0.11.5-1.fc43) has been pushed to the Fedora 43 stable repository.
If problem still persists, please make note of it in this bug report.

Comment 4 Fedora Update System 2026-07-23 01:20:26 UTC
FEDORA-2026-0e46c91ccf (libssh-0.12.1-1.fc44) has been pushed to the Fedora 44 stable repository.
If problem still persists, please make note of it in this bug report.


Note You need to log in before you can comment on or make changes to this bug.