CVE-2026-44950fs_read_glyphs() heap buffer overflow via cumulative glyph data overflow in libXfont2

9.5CriticalCVSS base score
0.26%Exploitation in 30 daysEPSS · top 82% of all CVEs
NoKnown exploitednot in CISA's KEV catalog
NonePublic exploitsnone known yet

Description

fs_read_glyphs() in the libXfont2 font-server client (src/fc/fserve.c) copies each glyph's bitmap into a single buffer. Existing checks validates only that the source slice (position, length) lies within the source bitmap buffer. It does not check whether the running destination cursor has exceeded the allocation. A malicious font server can send overlapping source offsets -- for example 1000 glyphs each referencing {position:0, length:64} with nbytes=64. Each individual source range passes the existing validation, but the cumulative writes total 64000 bytes into a 64-byte destination buffer. This is a heap buffer overflow with attacker-controlled content.

Timeline

2026
8 May 2026
8 May 2026
ID reserved
By suse
10 Sept 20264 months later
10 Sept 2026· 4 months later
Published

Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.

Scores

CVSS scores of CVE-2026-44950, by who scored it
Scored by	CVSS	Score	Vector
suseCNA (assigner)	4.0	Critical9.5	CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H
suseCNA (assigner)	3.1	Critical9.0	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H
NVDNVD · Awaiting Analysis	4.0	Critical9.5	CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

EPSS (exploitation in 30 days): 0.26% · top 82% of all CVEs (14 Nov 2026)
CISA SSVC: Exploitation: none · Automatable: no · Technical impact: total

The list uses the assigner's score when there is one, then CISA's, then NVD's: Critical 9.5.

Affected products

SUSE · Container suse/kiosk/tigervnc-x11vnc:1.14-63.8
- affected ? – < 2.0.3-150000.3.6.1
SUSE · Container suse/kiosk/xorg:21.1-83.7
- affected ? – < 2.0.3-150000.3.6.1
SUSE · Image SLES15-SP6-SAP
- affected ? – < 2.0.3-150000.3.6.1
SUSE · Image SLES15-SP6-SAP-Azure
- affected ? – < 2.0.3-150000.3.6.1
SUSE · Image SLES15-SP6-SAP-Azure-3P
- affected ? – < 2.0.3-150000.3.6.1
SUSE · Image SLES15-SP6-SAP-BYOS
- affected ? – < 2.0.3-150000.3.6.1
SUSE · Image SLES15-SP6-SAP-BYOS-Azure
- affected ? – < 2.0.3-150000.3.6.1
SUSE · Image SLES15-SP6-SAP-BYOS-EC2
- affected ? – < 2.0.3-150000.3.6.1
SUSE · Image SLES15-SP6-SAP-BYOS-GCE
- affected ? – < 2.0.3-150000.3.6.1
SUSE · Image SLES15-SP6-SAP-EC2
- affected ? – < 2.0.3-150000.3.6.1
SUSE · Image SLES15-SP6-SAP-GCE
- affected ? – < 2.0.3-150000.3.6.1
SUSE · Image SLES15-SP6-SAP-Hardened
- affected ? – < 2.0.3-150000.3.6.1
SUSE · Image SLES15-SP6-SAP-Hardened-Azure
- affected ? – < 2.0.3-150000.3.6.1
SUSE · Image SLES15-SP6-SAP-Hardened-BYOS
- affected ? – < 2.0.3-150000.3.6.1
SUSE · Image SLES15-SP6-SAP-Hardened-BYOS-Azure
- affected ? – < 2.0.3-150000.3.6.1
SUSE · Image SLES15-SP6-SAP-Hardened-BYOS-EC2
- affected ? – < 2.0.3-150000.3.6.1
SUSE · Image SLES15-SP6-SAP-Hardened-BYOS-GCE
- affected ? – < 2.0.3-150000.3.6.1
SUSE · Image SLES15-SP6-SAP-Hardened-EC2
- affected ? – < 2.0.3-150000.3.6.1
SUSE · Image SLES15-SP6-SAP-Hardened-GCE
- affected ? – < 2.0.3-150000.3.6.1
SUSE · Image SLES15-SP6-SAPCAL
- affected ? – < 2.0.3-150000.3.6.1
SUSE · Image SLES15-SP6-SAPCAL-Azure
- affected ? – < 2.0.3-150000.3.6.1
SUSE · Image SLES15-SP6-SAPCAL-EC2
- affected ? – < 2.0.3-150000.3.6.1
SUSE · Image SLES15-SP6-SAPCAL-GCE
- affected ? – < 2.0.3-150000.3.6.1
SUSE · Image SLES15-SP7-SAP-Azure
- affected ? – < 2.0.3-150000.3.6.1
SUSE · Image SLES15-SP7-SAP-Azure-3P
- affected ? – < 2.0.3-150000.3.6.1
SUSE · Image SLES15-SP7-SAP-BYOS-Azure
- affected ? – < 2.0.3-150000.3.6.1
SUSE · Image SLES15-SP7-SAP-BYOS-EC2
- affected ? – < 2.0.3-150000.3.6.1
SUSE · Image SLES15-SP7-SAP-BYOS-GCE
- affected ? – < 2.0.3-150000.3.6.1
SUSE · Image SLES15-SP7-SAP-EC2
- affected ? – < 2.0.3-150000.3.6.1
SUSE · Image SLES15-SP7-SAP-GCE
- affected ? – < 2.0.3-150000.3.6.1
SUSE · Image SLES15-SP7-SAP-GCE-3P
- affected ? – < 2.0.3-150000.3.6.1
SUSE · Image SLES15-SP7-SAP-Hardened-Azure
- affected ? – < 2.0.3-150000.3.6.1
SUSE · Image SLES15-SP7-SAP-Hardened-BYOS-Azure
- affected ? – < 2.0.3-150000.3.6.1
SUSE · Image SLES15-SP7-SAP-Hardened-BYOS-EC2
- affected ? – < 2.0.3-150000.3.6.1
SUSE · Image SLES15-SP7-SAP-Hardened-BYOS-GCE
- affected ? – < 2.0.3-150000.3.6.1
SUSE · Image SLES15-SP7-SAP-Hardened-GCE
- affected ? – < 2.0.3-150000.3.6.1
SUSE · Image SLES15-SP7-SAPCAL-Azure
- affected ? – < 2.0.3-150000.3.6.1
SUSE · Image SLES15-SP7-SAPCAL-EC2
- affected ? – < 2.0.3-150000.3.6.1
SUSE · Image SLES15-SP7-SAPCAL-GCE
- affected ? – < 2.0.3-150000.3.6.1
SUSE · Image SLES-SAP-Azure
- affected ? – < 2.0.7-160000.5.1
SUSE · Image SLES-SAP-Azure-3P
- affected ? – < 2.0.7-160000.5.1
SUSE · Image SLES-SAP-BYOS-Azure
- affected ? – < 2.0.7-160000.5.1
SUSE · Image SLES-SAP-BYOS-EC2
- affected ? – < 2.0.7-160000.5.1
SUSE · Image SLES-SAP-BYOS-GCE
- affected ? – < 2.0.7-160000.5.1
SUSE · Image SLES-SAP-GCE
- affected ? – < 2.0.7-160000.5.1
SUSE · Image SLES-SAP-GCE-3P
- affected ? – < 2.0.7-160000.5.1
SUSE · Image SLES-SAPCAL-GCE
- affected ? – < 2.0.7-160000.5.1
SUSE · Image SLES12-SP5-Azure-SAP-BYOS
- affected ? – < 2.0.3-3.6.1
SUSE · Image SLES12-SP5-Azure-SAP-On-Demand
- affected ? – < 2.0.3-3.6.1
SUSE · Image SLES12-SP5-EC2-SAP-BYOS
- affected ? – < 2.0.3-3.6.1
SUSE · Image SLES12-SP5-EC2-SAP-On-Demand
- affected ? – < 2.0.3-3.6.1
SUSE · Image SLES12-SP5-GCE-SAP-BYOS
- affected ? – < 2.0.3-3.6.1
SUSE · Image SLES12-SP5-GCE-SAP-On-Demand
- affected ? – < 2.0.3-3.6.1
SUSE · SUSE Liberty Linux 10
- affected ? – < 2.0.6-5.el10_2.3
SUSE · SUSE Liberty Linux 10
- affected ? – < 2.0.6-5.el10_2.3
SUSE · SUSE Liberty Linux 8
- affected ? – < 2.0.3-2.el8_10.3
SUSE · SUSE Liberty Linux 8
- affected ? – < 2.0.3-2.el8_10.3
SUSE · SUSE Liberty Linux 9
- affected ? – < 2.0.3-12.el9_8.3
SUSE · SUSE Liberty Linux 9
- affected ? – < 2.0.3-12.el9_8.3
SUSE · SUSE Linux Enterprise Desktop 15 SP7
- affected ? – < 2.0.3-150000.3.6.1
SUSE · SUSE Linux Enterprise Desktop 15 SP7
- affected ? – < 2.0.3-150000.3.6.1
SUSE · SUSE Linux Enterprise Module for Basesystem 15 SP7
- affected ? – < 2.0.3-150000.3.6.1
SUSE · SUSE Linux Enterprise Module for Basesystem 15 SP7
- affected ? – < 2.0.3-150000.3.6.1
SUSE · SUSE Linux Enterprise Server 15 SP7
- affected ? – < 2.0.3-150000.3.6.1
SUSE · SUSE Linux Enterprise Server 15 SP7
- affected ? – < 2.0.3-150000.3.6.1
SUSE · SUSE Linux Enterprise Server for SAP Applications 15 SP7
- affected ? – < 2.0.3-150000.3.6.1
SUSE · SUSE Linux Enterprise Server for SAP Applications 15 SP7
- affected ? – < 2.0.3-150000.3.6.1
SUSE · SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS
- affected ? – < 2.0.3-150000.3.6.1
SUSE · SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS
- affected ? – < 2.0.3-150000.3.6.1
SUSE · SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS
- affected ? – < 2.0.3-150000.3.6.1
SUSE · SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS
- affected ? – < 2.0.3-150000.3.6.1
SUSE · SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS
- affected ? – < 2.0.3-150000.3.6.1
SUSE · SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS
- affected ? – < 2.0.3-150000.3.6.1
SUSE · SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS
- affected ? – < 2.0.3-150000.3.6.1
SUSE · SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS
- affected ? – < 2.0.3-150000.3.6.1
SUSE · SUSE Linux Enterprise Server 12 SP5-LTSS
- affected ? – < 2.0.3-3.6.1
SUSE · SUSE Linux Enterprise Server 15 SP4-LTSS
- affected ? – < 2.0.3-150000.3.6.1
SUSE · SUSE Linux Enterprise Server 15 SP4-LTSS
- affected ? – < 2.0.3-150000.3.6.1
SUSE · SUSE Linux Enterprise Server 15 SP5-LTSS
- affected ? – < 2.0.3-150000.3.6.1
SUSE · SUSE Linux Enterprise Server 15 SP5-LTSS
- affected ? – < 2.0.3-150000.3.6.1
SUSE · SUSE Linux Enterprise Server 15 SP6-LTSS
- affected ? – < 2.0.3-150000.3.6.1
SUSE · SUSE Linux Enterprise Server 15 SP6-LTSS
- affected ? – < 2.0.3-150000.3.6.1
SUSE · SUSE Linux Enterprise Server 16.0
- affected ? – < 2.0.7-160000.5.1
SUSE · SUSE Linux Enterprise Server 16.0
- affected ? – < 2.0.7-160000.5.1
SUSE · SUSE Linux Enterprise Server for SAP applications 16.0
- affected ? – < 2.0.7-160000.5.1
SUSE · SUSE Linux Enterprise Server for SAP applications 16.0
- affected ? – < 2.0.7-160000.5.1
SUSE · SUSE Linux Enterprise Server LTSS Extended Security 12 SP5
- affected ? – < 2.0.3-3.6.1
SUSE · SUSE Linux Enterprise Server for SAP Applications 15 SP4
- affected ? – < 2.0.3-150000.3.6.1
SUSE · SUSE Linux Enterprise Server for SAP Applications 15 SP4
- affected ? – < 2.0.3-150000.3.6.1
SUSE · SUSE Linux Enterprise Server for SAP Applications 15 SP5
- affected ? – < 2.0.3-150000.3.6.1
SUSE · SUSE Linux Enterprise Server for SAP Applications 15 SP5
- affected ? – < 2.0.3-150000.3.6.1
SUSE · SUSE Linux Enterprise Server for SAP Applications 15 SP6
- affected ? – < 2.0.3-150000.3.6.1
SUSE · SUSE Linux Enterprise Server for SAP Applications 15 SP6
- affected ? – < 2.0.3-150000.3.6.1
SUSE · SUSE Manager Proxy LTS 4.3
- affected ? – < 2.0.3-150000.3.6.1
SUSE · SUSE Manager Proxy LTS 4.3
- affected ? – < 2.0.3-150000.3.6.1
SUSE · SUSE Manager Retail Branch Server LTS 4.3
- affected ? – < 2.0.3-150000.3.6.1
SUSE · SUSE Manager Retail Branch Server LTS 4.3
- affected ? – < 2.0.3-150000.3.6.1
SUSE · SUSE Manager Server LTS 4.3
- affected ? – < 2.0.3-150000.3.6.1
SUSE · SUSE Manager Server LTS 4.3
- affected ? – < 2.0.3-150000.3.6.1
SUSE · openSUSE Leap 16.0
- affected ? – < 2.0.7-160000.5.1
SUSE · openSUSE Leap 16.0
- affected ? – < 2.0.7-160000.5.1
SUSE · openSUSE Tumbleweed
- affected ? – < 2.0.7-3.1
SUSE · openSUSE Tumbleweed
- affected ? – < 2.0.7-3.1
SUSE · openSUSE Tumbleweed
- affected ? – < 2.0.7-3.1
SUSE · openSUSE Tumbleweed
- affected ? – < 2.0.7-3.1
libXfont · libXfont
- affected ? – ≤ 2.0.8

References1

https://bugzilla.suse.com/show_bug.cgi?id=CVE-2026-44950 (opens in a new tab)

Sources

The same CVE in the primary databases and aggregators, to check against.

Badge for a README or a ticket

[![CVE-2026-44950](https://cveledger.app/badge/CVE-2026-44950.svg)](https://cveledger.app/cve/CVE-2026-44950)

Record last updated 10 Sept 2026, 18:26 UTC.