CVE-2025-21433 in Snapdragon Auto
Summary
by MITRE • 07/08/2025
Transient DOS when importing a PKCS#8-encoded RSA private key with a zero-sized modulus.
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Analysis
by VulDB Data Team • 09/07/2025
This vulnerability involves a transient denial of service condition that occurs during the import process of PKCS#8-encoded RSA private keys when the modulus component has a zero size. The flaw exists within cryptographic libraries that handle PKCS#8 key format parsing and validation, specifically when processing RSA private keys where the modulus field contains invalid zero-length data. The issue manifests as a temporary system disruption that can affect applications relying on secure key management operations.
The technical root cause stems from insufficient input validation during the PKCS#8 key parsing process. When the cryptographic library attempts to import an RSA private key with a zero-sized modulus, the parsing routine fails to properly handle this edge case, leading to a temporary system hang or resource exhaustion. This vulnerability falls under CWE-129 Input Validation and CWE-248 Uncontrolled Resource Consumption, as the system becomes unresponsive due to malformed input processing. The zero-sized modulus represents an invalid mathematical component that should be rejected during validation but instead triggers an abnormal processing flow.
The operational impact of this vulnerability can be significant for systems that handle frequent key imports or cryptographic operations. Applications using affected cryptographic libraries may experience temporary service unavailability when processing maliciously crafted PKCS#8 key files. This transient nature makes the vulnerability particularly challenging to detect and mitigate, as it may not be immediately apparent during normal operation but can cause service disruptions during key management activities. The vulnerability affects systems that process external key material, including certificate authorities, key management systems, and any application that imports RSA private keys from external sources.
Mitigation strategies should focus on implementing robust input validation for PKCS#8 key imports and ensuring proper error handling during cryptographic key parsing operations. System administrators should update cryptographic libraries to versions that address this specific vulnerability and implement input sanitization measures that reject malformed key data before processing. Organizations should also consider implementing monitoring for unusual key import patterns and establish incident response procedures for handling transient service disruptions. The ATT&CK framework categorizes this vulnerability under T1499.004 Network Denial of Service and T1595.001 Network Share Discovery, as it affects the availability of cryptographic services through malformed input processing. Regular security assessments and penetration testing should include validation of key import functionality to identify similar edge case vulnerabilities in cryptographic implementations.