Bug 2543294

Summary:	CVE-2026-102560 libsoup3: libsoup: Heap buffer overflow during outgoing permessage-deflate buffer growth [fedora-all]
Product:	[Fedora] Fedora	Reporter:	Srikanth Balasubramanian <sbalasub>
Component:	libsoup3	Assignee:	Adrian Vovk <avovk>
Status:	CLOSED ERRATA	QA Contact:
Severity:	high	Docs Contact:
Priority:	high
Version:	44	CC:	avovk, gnome-sig, gwync, mcrha
Target Milestone:	---	Keywords:	Security, SecurityTracking
Target Release:	---
Hardware:	Unspecified
OS:	Unspecified
Whiteboard:	{"flaws": ["d377f1f6-75f0-49a4-9d3d-08f2be3de3fc"]}
Fixed In Version:	libsoup3-3.6.6-11.fc44	Doc Type:	---
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2026-11-03 01:38:26 UTC	Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description Srikanth Balasubramanian 2026-09-29 16:47:09 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 heap buffer overflow was found in libsoup's WebSocket permessage-deflate outgoing path.

soup_websocket_extension_deflate_process_outgoing_message() stored deflateBound()'s uLong result in a guint and grew a GByteArray by that amount. For payloads approaching 4 GiB, the bound exceeds G_MAXUINT; truncation allowed buffer->len + max_length to wrap on later growth, and zlib wrote through next_out past the allocation.

Fixed by refusing payloads whose compressed bound cannot fit in a GByteArray and by checking each incremental growth (commit dbd0417e, libsoup 3.7.3).

References:
https://gitlab.gnome.org/GNOME/libsoup/-/work_items/554 (Bug 8)
https://gitlab.gnome.org/GNOME/libsoup/-/commit/dbd0417e

Comment 1 Adrian Vovk 2026-10-27 00:51:23 UTC

rawhide and f45 will be fixed by upgrading to 3.8 w/ mclazy

f44 and f43 will need a backport of the commit

Comment 2 Fedora Update System 2026-10-27 05:13:14 UTC

FEDORA-2026-6c3a4775a6 (libsoup3-3.6.6-6.fc43) has been submitted as an update to Fedora 43.
https://bodhi.fedoraproject.org/updates/FEDORA-2026-6c3a4775a6

Comment 3 Fedora Update System 2026-10-27 05:13:45 UTC

FEDORA-2026-f06a7887af (libsoup3-3.6.6-11.fc44) has been submitted as an update to Fedora 44.
https://bodhi.fedoraproject.org/updates/FEDORA-2026-f06a7887af

Comment 4 Fedora Update System 2026-10-28 03:18:16 UTC

FEDORA-2026-6c3a4775a6 has been pushed to the Fedora 43 testing repository.
Soon you'll be able to install the update with the following command:
`sudo dnf upgrade --enablerepo=updates-testing --refresh --advisory=FEDORA-2026-6c3a4775a6`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2026-6c3a4775a6

See also https://fedoraproject.org/wiki/QA:Updates_Testing for more information on how to test updates.

Comment 5 Fedora Update System 2026-10-28 04:01:23 UTC

FEDORA-2026-f06a7887af has been pushed to the Fedora 44 testing repository.
Soon you'll be able to install the update with the following command:
`sudo dnf upgrade --enablerepo=updates-testing --refresh --advisory=FEDORA-2026-f06a7887af`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2026-f06a7887af

See also https://fedoraproject.org/wiki/QA:Updates_Testing for more information on how to test updates.

Comment 6 Fedora Update System 2026-11-03 01:38:26 UTC

FEDORA-2026-f06a7887af (libsoup3-3.6.6-11.fc44) has been pushed to the Fedora 44 stable repository.
If problem still persists, please make note of it in this bug report.