CVE-2025-10699 Overview
CVE-2025-10699 is an information disclosure vulnerability in the Lenovo LeCloud client application. The flaw is categorized under [CWE-295] Improper Certificate Validation. Under certain conditions, the client fails to properly validate server certificates, which can allow an attacker positioned on the network path to intercept confidential data exchanged between the client and Lenovo cloud services.
The vulnerability requires user interaction and passive attack prerequisites, but no privileges on the target system. Successful exploitation results in high confidentiality impact with no direct effect on integrity or availability.
Critical Impact
An attacker capable of intercepting client-to-server traffic can decrypt or read sensitive information transmitted by the Lenovo LeCloud client due to insufficient TLS certificate validation.
Affected Products
- Lenovo LeCloud client application
- Lenovo Cloud Platform (LeCloud) service endpoints consumed by the vulnerable client
- Refer to Lenovo Product Detail #432379 for specific affected builds
Discovery Timeline
- 2025-10-15 - CVE-2025-10699 published to NVD
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2025-10699
Vulnerability Analysis
The vulnerability stems from improper certificate validation in the Lenovo LeCloud client. The application does not correctly verify the authenticity of TLS certificates presented by remote servers during secure communication. This weakness maps to [CWE-295] and enables man-in-the-middle (MITM) conditions.
When a client fails to validate a certificate chain, revocation status, hostname, or trusted root anchor, an attacker who controls a network segment can present a substitute certificate. The client accepts the connection and continues to transmit authentication material, session tokens, or user data over what it believes is a trusted channel.
The attack requires network positioning and user interaction, meaning the victim must launch or use the LeCloud client while the attacker is intercepting traffic. Exploitation does not require credentials on the target device.
Root Cause
The root cause is insufficient validation logic in the client's TLS handshake path. Common patterns behind [CWE-295] include disabled hostname verification, acceptance of self-signed certificates, use of a permissive trust manager, or failure to check certificate revocation. Any of these conditions permits a forged certificate to be accepted as valid.
Attack Vector
An attacker positions on the same network as the victim, for example a shared Wi-Fi network or a compromised upstream router. The attacker intercepts LeCloud client traffic and presents a crafted TLS certificate. The client establishes a session with the attacker-controlled endpoint and transmits confidential data. The attacker records or forwards the data to legitimate Lenovo servers to keep the session functional.
No verified public proof-of-concept code is available for this vulnerability. Refer to the Lenovo Product Detail #432379 advisory for vendor-supplied technical context.
Detection Methods for CVE-2025-10699
Indicators of Compromise
- Unexpected TLS certificates presented for Lenovo LeCloud domains that do not chain to Lenovo's issuing certificate authority
- Anomalous DNS responses for LeCloud endpoints resolving to non-Lenovo infrastructure
- LeCloud client sessions terminating and reconnecting through unusual intermediate hosts
Detection Strategies
- Perform TLS inspection on egress traffic and alert when the LeCloud client connects to endpoints presenting untrusted or pinned-mismatch certificates
- Baseline the expected certificate fingerprints for Lenovo cloud endpoints and alert on deviation
- Correlate endpoint process telemetry showing the LeCloud client executing with concurrent ARP spoofing or rogue DHCP activity on the same subnet
Monitoring Recommendations
- Log all outbound TLS handshakes originating from the LeCloud client binary and retain certificate metadata for review
- Monitor for hosts operating on untrusted networks such as public Wi-Fi where the LeCloud client is active
- Track user endpoints for repeated authentication events to LeCloud services that may indicate session replay
How to Mitigate CVE-2025-10699
Immediate Actions Required
- Update the Lenovo LeCloud client to the version specified in the vendor advisory as soon as it is available
- Restrict use of the LeCloud client to trusted networks until patching is complete
- Enforce enterprise VPN usage for endpoints that must access LeCloud services from untrusted networks
Patch Information
Lenovo has published guidance in Lenovo Product Detail #432379. Administrators should consult this reference for the fixed client version and deployment instructions. Additional service information is available on the Lenovo Cloud Platform page.
Workarounds
- Block or restrict LeCloud client execution on managed endpoints until the updated client is deployed
- Require all client traffic to traverse a corporate proxy that enforces strict certificate validation
- Educate users to avoid using the LeCloud client on public or untrusted wireless networks
# Example: block the LeCloud client from launching on managed Windows endpoints
# using an AppLocker publisher rule until the patched version is deployed
New-AppLockerPolicy -RuleType Publisher -User Everyone -Action Deny `
-FilePath "C:\Program Files\Lenovo\LeCloud\LeCloud.exe"
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
