X.org X11 Server TigerVNC RecordSanityCheckRegisterClients integer overflow

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.2$0-$5k0.00

Summaryinfo

A vulnerability classified as problematic has been found in X.org X11 Server. The impacted element is the function RecordSanityCheckRegisterClients of the component TigerVNC. Performing a manipulation results in integer overflow. This vulnerability is cataloged as CVE-2025-49179. The attack must be initiated from a local position. There is no exploit available.

Detailsinfo

A vulnerability classified as problematic has been found in X.org X11 Server (version now known). This affects the function RecordSanityCheckRegisterClients of the component TigerVNC. The manipulation with an unknown input leads to a integer overflow vulnerability. CWE is classifying the issue as CWE-190. The product performs a calculation that can produce an integer overflow or wraparound, when the logic assumes that the resulting value will always be larger than the original value. This can introduce other weaknesses when the calculation is used for resource management or execution control. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

A flaw was found in the X Record extension. The RecordSanityCheckRegisterClients function does not check for an integer overflow when computing request length, which allows a client to bypass length checks.

It is possible to read the advisory at access.redhat.com. This vulnerability is uniquely identified as CVE-2025-49179 since 06/03/2025. The exploitability is told to be easy. Attacking locally is a requirement. Technical details of the vulnerability are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 240228 (Fedora 42 : xorg-x11-server-Xwayland (2025-b4d521f084)), which helps to determine the existence of the flaw in a target environment.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the databases at Tenable (240228) and EUVD (EUVD-2025-18500). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 6.2

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

CNA Base Score: 7.3
CNA Vector (redhat): 🔍

CVSSv2info

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

Exploitinginfo

Class: Integer overflow
CWE: CWE-190 / CWE-189
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: No

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 240228
Nessus Name: Fedora 42 : xorg-x11-server-Xwayland (2025-b4d521f084)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔍

Timelineinfo

06/03/2025 🔍
06/17/2025 +14 days 🔍
06/17/2025 +0 days 🔍
06/30/2025 +13 days 🔍

Sourcesinfo

Vendor: x.org

Advisory: access.redhat.com
Status: Not defined

CVE: CVE-2025-49179 (🔍)
GCVE (CVE): GCVE-0-2025-49179
GCVE (VulDB): GCVE-100-312759
EUVD: 🔍

Entryinfo

Created: 06/17/2025 18:18
Updated: 06/30/2025 11:27
Changes: 06/17/2025 18:18 (62), 06/17/2025 18:36 (1), 06/21/2025 17:35 (2), 06/23/2025 09:21 (1), 06/30/2025 11:27 (4)
Complete: 🔍
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

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