X.Org libXfont2 up to 2.0.7 PCF file Parser ComputeScaledProperties heap-based overflow

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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9.5$0-$5k0.60+

Summaryinfo

A vulnerability marked as very critical has been reported in X.Org libXfont2 up to 2.0.7. Impacted is the function ComputeScaledProperties of the component PCF file Parser. Performing a manipulation results in heap-based overflow. This vulnerability is identified as CVE-2026-56003. The attack can be initiated remotely. There is not any exploit available.

Detailsinfo

A vulnerability classified as very critical has been found in X.Org libXfont2 up to 2.0.7. This affects the function ComputeScaledProperties of the component PCF file Parser. The manipulation with an unknown input leads to a heap-based overflow vulnerability. CWE is classifying the issue as CWE-122. A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc(). This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

A heap buffer overflow due to missing size checking in the property buffer when parsing PCF files in libXfont2 ComputeScaledProperties() before libXfont2 before 2.0.8 could be used by attackers using authenticated X clients to execute code within the X server.

The advisory is shared at openwall.com. This vulnerability is uniquely identified as CVE-2026-56003 since 06/18/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. Technical details are known, but no exploit is available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 07/08/2026).

Upgrading to version 2.0.8 eliminates this vulnerability.

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Vendor

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Version

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Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 9.9
VulDB Meta Temp Score: 9.5

VulDB Base Score: 9.9
VulDB Temp Score: 9.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Heap-based overflow
CWE: CWE-122 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Upgrade: libXfont2 2.0.8

Timelineinfo

06/18/2026 CVE reserved
07/08/2026 +20 days Advisory disclosed
07/08/2026 +0 days VulDB entry created
07/08/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: x.org

Advisory: openwall.com
Status: Confirmed

CVE: CVE-2026-56003 (🔒)
GCVE (CVE): GCVE-0-2026-56003
GCVE (VulDB): GCVE-100-376821

Entryinfo

Created: 07/08/2026 12:16
Changes: 07/08/2026 12:16 (54)
Complete: 🔍
Cache ID: 216::103

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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