CVE-2017-18146 in Android
Summary
by MITRE
In Android before security patch level 2018-04-05 on Qualcomm Snapdragon Automobile, Snapdragon Mobile, and Snapdragon Wear MDM9206, MDM9607, MDM9650, MSM8909W, SD 210/SD 212/SD 205, SD 400, SD 410/12, SD 425, SD 430, SD 450, SD 615/16/SD 415, SD 617, SD 625, SD 650/52, SD 800, SD 808, SD 810, SD 820, SD 820A, SD 835, SD 845, SD 850, in some corner cases, ECDSA signature verification can fail.
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Analysis
by VulDB Data Team • 01/24/2020
This vulnerability affects Android devices running Qualcomm Snapdragon chipsets and represents a cryptographic flaw in the elliptic curve digital signature algorithm implementation. The issue manifests in specific corner cases where ECDSA signature verification fails, potentially allowing attackers to bypass security mechanisms that rely on digital signatures for authentication and integrity validation. The vulnerability exists across multiple Snapdragon chipset variants including MDM9206, MDM9607, MDM9650, MSM8909W, and various SD series processors, indicating a widespread impact across automotive, mobile, and wearable device categories. This flaw falls under CWE-330 Use of Insufficiently Random Values, as it involves cryptographic weaknesses that could be exploited through predictable or improperly handled signature verification processes.
The operational impact of this vulnerability extends beyond simple signature verification failures, as it could enable malicious actors to forge digital signatures or bypass authentication mechanisms that depend on ECDSA validation. Attackers could potentially exploit this weakness to compromise secure communications, install unauthorized applications, or gain elevated privileges on affected devices. The vulnerability's presence in automotive systems particularly raises concerns about vehicle security and the potential for remote code execution or unauthorized access to critical vehicle functions. This aligns with ATT&CK technique T1547.001 for Registry Run Keys / Startup Folder and T1059 for Command and Scripting Interpreter, as compromised signature verification could enable persistent threats and execution of malicious code.
Security researchers have identified that the flaw occurs in the corner cases of ECDSA implementation, suggesting that the cryptographic library may not properly handle certain edge conditions during signature validation. This could involve improper handling of curve parameters, invalid signature values, or edge case scenarios that should normally be rejected by proper cryptographic implementations. The vulnerability's timing in relation to the 2018-04-05 security patch level indicates that Qualcomm and Google recognized the severity of the issue and addressed it through firmware and system updates. Organizations should implement immediate patch management procedures to ensure all affected devices receive the necessary security updates. The vulnerability also highlights the importance of comprehensive cryptographic testing, particularly for edge cases in signature verification algorithms, as outlined in NIST SP 800-57 guidelines for cryptographic key management and validation processes.
The widespread nature of this vulnerability across multiple chipset generations suggests that proper cryptographic implementation practices were not consistently applied across Qualcomm's product line. This represents a significant concern for device manufacturers and security teams who must account for potential exploitation across various hardware platforms. The issue also demonstrates the critical importance of thorough security testing for cryptographic implementations, particularly in automotive environments where security failures could have severe consequences. Device manufacturers should consider implementing additional security controls beyond the basic signature verification mechanisms, including hardware-based security features and enhanced cryptographic validation routines to prevent similar vulnerabilities in future implementations.