CVE-2026-56001: libXfont2 BitmapScaleBitmaps Integer Overflow Heap Buffer Overflow
Noroxi assessment
Priority: Monitor (action score 35/100)
- The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
- Probability of exploitation in the next 30 days: 0.39% (FIRST EPSS).
- Anyone who can reach it over the internet can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
- Fixed version: X.Org libXfont2 2.0.8; azl3 libXfont2 2.0.6-1 on Azure Linux 3.0 2.0.8-1.
Low priority for now. Upgrade to X.Org libXfont2 2.0.8; azl3 libXfont2 2.0.6-1 on Azure Linux 3.0 2.0.8-1 or later.
Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it
Primary sources: NVD · CVE.org · FIRST EPSS
A heap buffer overflow in BitmapScaleBitmaps in libXfont2 before 2.0.8 due to an overflowing 32bit size could be used by attackers able to access the X Server to execute code within the X server cont
- ALSA-2026:47079
- ALSA-2026:47084
- ALSA-2026:47103
- openSUSE-SU-2026:11233-1
- openSUSE-SU-2026:21284-1
- RHSA-2026:47079
- RHSA-2026:47084
- RHSA-2026:47103
- RHSA-2026:51058
- RHSA-2026:51059
- RHSA-2026:51060
- RHSA-2026:51061
- RHSA-2026:51062
- RHSA-2026:51063
- RHSA-2026:51066
- RHSA-2026:51067
- RLSA-2026:47079
- RLSA-2026:47084
- RLSA-2026:47103
- SUSE-SU-2026:22614-1
- Published
- Jul 8, 2026
- Updated
- Oct 25, 2026
- EPSS
- 0.3% · 33th percentile
- CWE
- CWE-122
Report tools
Action score
35
Low priority for now.
- CVSS
- 35 / 40 · 8.8 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.3%
CISA SSVC decision
- Exploitation
- none
- Automatable
- no
- Technical impact
- total
Vulnrichment: CISA's decision-tree inputs.
CNA vs NVD score
- NVD
- 8.8
- CNA · suse
- 8.5
- 0.3 point gap
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
Get told when this record changes
- Not in KEV: no record of exploitation in the wild
- No public exploit code on record
- A fix has been released
If any of these changes, we'll tell you in the daily email digest.
Is your version affected? Check itNoroxi analysis
What does it mean in your environment?
The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.
We use this product, ask for helpAffected systems
Is your version affected?
Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.
| Vendor | Product | CPE |
|---|---|---|
| x | libxfont | cpe:2.3:a:x:libxfont |
Versions reported by the vendor
Affected version ranges reported by the assigning authority (suse). Independent of NVD's CPE analysis and usually ahead of it.
X.Org libXfont2
- before 2.0.8affected · rpm
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- x libxfont2.0.0 and later · before 2.0.8
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| AlmaLinux:10 | libXfont2 | before 2.0.6-5.el10_2.1 | 2.0.6-5.el10_2.1 |
| AlmaLinux:10 | libXfont2-devel | before 2.0.6-5.el10_2.1 | 2.0.6-5.el10_2.1 |
| AlmaLinux:8 | libXfont2 | before 2.0.3-2.el8_10.1 | 2.0.3-2.el8_10.1 |
| AlmaLinux:8 | libXfont2-devel | before 2.0.3-2.el8_10.1 | 2.0.3-2.el8_10.1 |
| AlmaLinux:9 | libXfont2 | before 2.0.3-12.el9_8.1 | 2.0.3-12.el9_8.1 |
| AlmaLinux:9 | libXfont2-devel | before 2.0.3-12.el9_8.1 | 2.0.3-12.el9_8.1 |
| Alpine:v3.24 | libxfont2 | before 2.0.8-r0 | 2.0.8-r0 |
| Debian:12 | libxfont | before 1:2.0.6-1+deb12u1 | 1:2.0.6-1+deb12u1 |
| Debian:13 | libxfont | before 1:2.0.6-1+deb13u1 | 1:2.0.6-1+deb13u1 |
| Debian:14 | libxfont | before 1:2.0.8-1 | 1:2.0.8-1 |
| openSUSE:Leap 16.0 | libXfont2 | before 2.0.7-160000.4.1 | 2.0.7-160000.4.1 |
| openSUSE:Tumbleweed | libXfont2 | before 2.0.7-2.1 | 2.0.7-2.1 |
| Red Hat:enterprise_linux_eus:10.0 | libXfont2 | before 0:2.0.6-5.el10_0.1 | 0:2.0.6-5.el10_0.1 |
| Red Hat:enterprise_linux_eus:10.0 | libXfont2-debuginfo | before 0:2.0.6-5.el10_0.1 | 0:2.0.6-5.el10_0.1 |
| Red Hat:enterprise_linux_eus:10.0 | libXfont2-debugsource | before 0:2.0.6-5.el10_0.1 | 0:2.0.6-5.el10_0.1 |
| Red Hat:enterprise_linux_eus:10.0 | libXfont2-devel | before 0:2.0.6-5.el10_0.1 | 0:2.0.6-5.el10_0.1 |
| Red Hat:enterprise_linux:10.2 | libXfont2 | before 0:2.0.6-5.el10_2.1 | 0:2.0.6-5.el10_2.1 |
| Red Hat:enterprise_linux:10.2 | libXfont2-debuginfo | before 0:2.0.6-5.el10_2.1 | 0:2.0.6-5.el10_2.1 |
| Red Hat:enterprise_linux:10.2 | libXfont2-debugsource | before 0:2.0.6-5.el10_2.1 | 0:2.0.6-5.el10_2.1 |
| Red Hat:enterprise_linux:10.2 | libXfont2-devel | before 0:2.0.6-5.el10_2.1 | 0:2.0.6-5.el10_2.1 |
| Red Hat:enterprise_linux:8::appstream | libXfont2 | before 0:2.0.3-2.el8_10.1 | 0:2.0.3-2.el8_10.1 |
| Red Hat:enterprise_linux:8::appstream | libXfont2-debuginfo | before 0:2.0.3-2.el8_10.1 | 0:2.0.3-2.el8_10.1 |
| Red Hat:enterprise_linux:8::appstream | libXfont2-debugsource | before 0:2.0.3-2.el8_10.1 | 0:2.0.3-2.el8_10.1 |
| Red Hat:enterprise_linux:8::crb | libXfont2-devel | before 0:2.0.3-2.el8_10.1 | 0:2.0.3-2.el8_10.1 |
+32
Same product
x: all recordsOther highest-scoring records for the same primary product.
- CVE-2007-5199A single byte overflow in catalogue.c in X.Org libXfont 1.3.1 allows remote attackers to have unspecified impact.40Plan
- CVE-2013-6462Stack-based buffer overflow in the bdfReadCharacters function in bitmap/bdfread.c in X.Org libXfont 1.1 through 1.4.6 allows remote…40Plan
- CVE-2011-2895The LZW decompressor in (1) the BufCompressedFill function in fontfile/decompress.c in X.Org libXfont before 1.4.4 and (2)…40Plan
Published before and after this one in the same product
- ← EarlierCVE-2015-1804Mar 20, 2015 · The bdfReadCharacters function in bitmap/bdfread.c in X.Org libXfont before 1.4.9 and 1.5.x before 1.5.1 does not properly perform type…35Monitor
- ← EarlierCVE-2017-16611Dec 1, 2017 · In libXfont before 1.5.4 and libXfont2 before 2.0.3, a local attacker can open (but not read) files on the system as root, triggering tape…22Monitor
- Later →CVE-2026-56002Jul 8, 2026 · libXfont2 PCF Font Parsing Heap Buffer Overflow35Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| X.Org libXfont2 | 2.0.8 | Vendor (CNA) |
| azl3 libXfont2 2.0.6-1 on Azure Linux 3.0 | 2.0.8-1 · CBL-Mariner Releases | Microsoft (MSRC) |
| almalinux:libXfont2 | 2.0.6-5.el10_2.1 · AlmaLinux:10 | Package registry (OSV) |
| almalinux:libXfont2-devel | 2.0.6-5.el10_2.1 · AlmaLinux:10 | Package registry (OSV) |
| alpine:libxfont2 | 2.0.8-r0 · Alpine:v3.24 | Package registry (OSV) |
| debian:libxfont | 1:2.0.6-1+deb12u1 · Debian:12 | Package registry (OSV) |
| opensuse:libXfont2 | 2.0.7-2.1 · openSUSE:Tumbleweed | Package registry (OSV) |
| red hat:libXfont2 | 0:2.0.6-5.el10_2.1 · Red Hat:enterprise_linux:10.2 | Package registry (OSV) |
| red hat:libXfont2-debuginfo | 0:2.0.6-5.el10_2.1 · Red Hat:enterprise_linux:10.2 | Package registry (OSV) |
| red hat:libXfont2-debugsource | 0:2.0.6-5.el10_2.1 · Red Hat:enterprise_linux:10.2 | Package registry (OSV) |
| red hat:libXfont2-devel | 0:2.0.6-5.el10_2.1 · Red Hat:enterprise_linux:10.2 | Package registry (OSV) |
| rocky linux:libXfont2 | 0:2.0.6-5.el10_2.1 · Rocky Linux:10 | Package registry (OSV) |
| suse:libXfont2 | 2.0.7-160000.4.1 · SUSE:Linux Enterprise Server 16.0 | Package registry (OSV) |
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
- CVE-2026-560020 days apartlibXfont2 PCF Font Parsing Heap Buffer Overflow35Monitor
- CVE-2026-560030 days apartlibXfont2 computeProps Property Buffer Heap Buffer Overflow35Monitor
Not on record for this CVE: EPSS history · public bounty program.
Technical details
Attack conditions
- Anyone who can reach it over the internet can trigger it.
- A low-privileged account is enough.
- No user action is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- high · data can be read
- Integrity
- high · data or configuration can be modified
- Availability
- high · the service can be disrupted
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- High
- Integrity impact
- High
- Availability impact
- High
Weakness class (CWE)
CWE-122 · Heap-based Buffer OverflowCVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
nvd-primary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
Attack patterns (CAPEC)
ATT&CK techniques
—
Change log (1)
- Fix✗ → ✓
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References
Show all references (1 more)Show less
Vendor advisories and official records. Exploit/PoC links are deliberately left out.