Insyde H2O up to 5.7 on Lenovo EfiSmiServices out-of-bounds write

CVSS Meta Temp Score
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CTI Interest Score
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7.1$0-$5k0.00

Summaryinfo

A vulnerability was found in Insyde H2O on Lenovo and classified as critical. This vulnerability affects unknown code of the component EfiSmiServices. Executing a manipulation can lead to out-of-bounds write. This vulnerability is tracked as CVE-2025-4421. The attack is restricted to local execution. No exploit exists. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in Insyde H2O on Lenovo. It has been declared as critical. This vulnerability affects an unknown code of the component EfiSmiServices. The manipulation with an unknown input leads to a out-of-bounds write vulnerability. The CWE definition for the vulnerability is CWE-787. The product writes data past the end, or before the beginning, of the intended buffer. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

The vulnerability was identified in the code developed specifically for Lenovo. Please visit "Lenovo Product Security Advisories and Announcements" webpage for more information about the vulnerability.  https://support.lenovo.com/us/en/product_security/home

The advisory is shared for download at insyde.com. This vulnerability was named CVE-2025-4421 since 05/08/2025. The exploitation appears to be difficult. The attack needs to be approached locally. Additional levels of successful authentication are required for exploitation. There are neither technical details nor an exploit publicly available.

Upgrading to version L05.05.40.011803.172079 eliminates this vulnerability.

VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

Vendor

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.3
VulDB Meta Temp Score: 7.1

VulDB Base Score: 6.4
VulDB Temp Score: 6.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 8.2
CNA Vector (Insyde): 🔒

CVSSv2info

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

Exploitinginfo

Class: Out-of-bounds write
CWE: CWE-787 / CWE-119
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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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: H2O L05.05.40.011803.172079

Timelineinfo

05/08/2025 CVE reserved
07/30/2025 +83 days Advisory disclosed
07/30/2025 +0 days VulDB entry created
07/30/2025 +0 days VulDB entry last update

Sourcesinfo

Advisory: insyde.com
Status: Confirmed

CVE: CVE-2025-4421 (🔒)
GCVE (CVE): GCVE-0-2025-4421
GCVE (VulDB): GCVE-100-318112

Entryinfo

Created: 07/30/2025 08:13
Changes: 07/30/2025 08:13 (65)
Complete: 🔍
Cache ID: 216::103

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