Upstream information

CVE-2026-77658 at MITRE

Description

A stack-based buffer overflow vulnerability exists in the Dia diagram editor when processing Network Bus objects from Dia XML project files.

In objects/network/bus.c, bus_load() reads the number of bus handles from the file attribute "bus_handles" using attribute_num_data() without validating an upper bound:

bus->num_handles = attribute_num_data(attr);

When a bus handle is subsequently moved, bus_handle_moved() allocates two temporary arrays on the stack:

parallel = (real *)g_alloca(num_handles * sizeof(real));
perp = (real *)g_alloca(num_handles * sizeof(real));

Because num_handles is fully attacker-controlled via the project file, sufficiently large values (for example 262144 or higher) cause g_alloca() to consume more stack space than the default thread stack limit (typically 8 MB on Linux), resulting in stack overflow, SIGSEGV, and potential stack frame / return-address corruption.

An attacker can embed a Bus object with an excessive bus_handles count in a malicious .dia file. Exploitation requires the victim to open the file in Dia (file dialog, command line, or file association) and trigger handle manipulation (moving a bus handle), which exercises the vulnerable code path.

The identical g_alloca pattern is present in objects/Misc/tree.c (copied from bus.c) and is likely vulnerable to the same class of attack via Tree objects.

Affected versions: Dia 0.98.0 and earlier versions containing this code; issue confirmed on upstream master as of 2026-08-21.
Upstream report: https://gitlab.gnome.org/GNOME/dia/-/issues/581

SUSE information

Overall state of this security issue: Pending

This issue is currently rated as having important severity.

CVSS v3 Scores
CVSS detail CNA (Fedora Project) SUSE
Base Score 7.8 7.8
Vector CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Attack Vector Local Local
Attack Complexity Low Low
Privileges Required None None
User Interaction Required Required
Scope Unchanged Unchanged
Confidentiality Impact High High
Integrity Impact High High
Availability Impact High High
CVSSv3 Version 3.1 3.1
SUSE Bugzilla entry: 1276757 [NEW]

No SUSE Security Announcements cross referenced.


Status of this issue by product and package

Please note that this evaluation state might be work in progress, incomplete or outdated. Also information for service packs in the LTSS phase is only included for issues meeting the LTSS criteria. If in doubt, feel free to contact us for clarification. The updates are grouped by state of their lifecycle. SUSE product lifecycles are documented on the lifecycle page.

Product(s) Source package State
Products under general support and receiving all security fixes.
SUSE Linux Enterprise Desktop 15 SP7 dia Affected
SUSE Linux Enterprise Module for Package Hub 15 SP7 dia Affected
SUSE Linux Enterprise Server 15 SP7 dia Affected
SUSE Linux Enterprise Server for SAP Applications 15 SP7 dia Affected
SUSE Linux Enterprise Workstation Extension 15 SP7 dia Affected
Products under Long Term Service Pack support and receiving important and critical security fixes.
SUSE Linux Enterprise Server 15 SP4 dia Affected
SUSE Linux Enterprise Server 15 SP5 dia Affected
SUSE Linux Enterprise Server 15 SP6 dia Affected
SUSE Linux Enterprise Server for SAP Applications 15 SP4 dia Affected
SUSE Linux Enterprise Server for SAP Applications 15 SP5 dia Affected
SUSE Linux Enterprise Server for SAP Applications 15 SP6 dia Affected
Products past their end of life and not receiving proactive updates anymore.
SUSE Linux Enterprise Desktop 15 dia Affected
SUSE Linux Enterprise Desktop 15 SP1 dia Affected
SUSE Linux Enterprise Desktop 15 SP2 dia Affected
SUSE Linux Enterprise Desktop 15 SP3 dia Affected
SUSE Linux Enterprise Desktop 15 SP4 dia Affected
SUSE Linux Enterprise Desktop 15 SP5 dia Affected
SUSE Linux Enterprise Desktop 15 SP6 dia Affected
SUSE Linux Enterprise Module for Package Hub 15 SP3 dia Affected
SUSE Linux Enterprise Module for Package Hub 15 SP4 dia Affected
SUSE Linux Enterprise Module for Package Hub 15 SP5 dia Affected
SUSE Linux Enterprise Module for Package Hub 15 SP6 dia Affected
SUSE Linux Enterprise Server 15 dia Affected
SUSE Linux Enterprise Server 15 SP1 dia Affected
SUSE Linux Enterprise Server 15 SP2 dia Affected
SUSE Linux Enterprise Server 15 SP3 dia Affected
SUSE Linux Enterprise Server for SAP Applications 15 dia Affected
SUSE Linux Enterprise Server for SAP Applications 15 SP1 dia Affected
SUSE Linux Enterprise Server for SAP Applications 15 SP2 dia Affected
SUSE Linux Enterprise Server for SAP Applications 15 SP3 dia Affected
SUSE Linux Enterprise Workstation Extension 15 dia Affected
SUSE Linux Enterprise Workstation Extension 15 SP1 dia Affected
SUSE Linux Enterprise Workstation Extension 15 SP2 dia Affected
SUSE Linux Enterprise Workstation Extension 15 SP3 dia Affected
SUSE Linux Enterprise Workstation Extension 15 SP4 dia Affected
SUSE Linux Enterprise Workstation Extension 15 SP5 dia Affected
SUSE Linux Enterprise Workstation Extension 15 SP6 dia Affected
openSUSE Leap 15.3 dia Affected
openSUSE Leap 15.4 dia Affected
openSUSE Leap 15.5 dia Affected
openSUSE Leap 15.6 dia Affected


SUSE Timeline for this CVE

CVE page created: Wed Aug 26 11:48:15 2026
CVE page last modified: Wed Aug 26 21:53:20 2026