CVE-2025-58185 is a vulnerability classified under CWE-400 (Uncontrolled Resource Consumption) found in the Go standard library's encoding/asn1 package. The issue occurs when the ASN.1 DER parser processes a maliciously crafted payload that triggers excessive memory allocation. ASN.1 (Abstract Syntax Notation One) is widely used for encoding data structures in cryptographic certificates, network protocols, and other security-related applications. The vulnerability allows an attacker to supply a DER-encoded input that causes the parser to allocate large amounts of memory without proper bounds checking or limits, leading to memory exhaustion. This can result in denial of service (DoS) by crashing the application or degrading system performance. The vulnerability affects all Go versions up to and including 1.25.0, with no patch currently available as of the published date. No exploits have been reported in the wild, but the flaw is straightforward to trigger if an attacker can supply ASN.1 data to a vulnerable application. The attack vector requires the application to parse untrusted ASN.1 DER data, which is common in systems handling certificates, cryptographic tokens, or network messages. Because ASN.1 is a fundamental encoding standard in many security protocols, this vulnerability has broad implications for any Go-based software performing ASN.1 parsing. The lack of authentication requirement and the potential for remote triggering increase the risk profile. The vulnerability highlights the need for robust input validation and resource management in parsers handling complex data formats.

For European organizations, the primary impact of CVE-2025-58185 is the risk of denial of service through memory exhaustion, which can disrupt critical services relying on Go applications that parse ASN.1 data. This includes systems involved in certificate validation, cryptographic operations, secure communications, and network protocol implementations. Disruption of these services can affect financial institutions, government agencies, telecommunications providers, and cloud service operators. The memory exhaustion could lead to application crashes, degraded performance, or system instability, potentially causing downtime and impacting business continuity. Additionally, if exploited in environments handling sensitive data, it may indirectly affect data integrity and availability. Given the widespread use of Go in modern cloud-native and microservices architectures, the vulnerability could have cascading effects in complex IT environments. The absence of known exploits provides a window for proactive mitigation, but the ease of triggering the vulnerability means attackers could weaponize it quickly once details become public. Organizations with high reliance on Go-based infrastructure and those processing untrusted ASN.1 data are particularly vulnerable.

1. Monitor for official patches or updates from the Go project and apply them promptly once available. 2. Until a patch is released, implement strict input validation to reject malformed or suspicious ASN.1 DER payloads before parsing. 3. Employ resource limiting techniques such as memory quotas or sandboxing for processes handling ASN.1 data to prevent excessive resource consumption. 4. Use application-layer firewalls or intrusion detection systems to detect and block anomalous ASN.1 payloads or traffic patterns. 5. Review and audit all code paths that parse ASN.1 data to ensure they do not process untrusted inputs without validation. 6. Consider isolating ASN.1 parsing functionality into separate processes or containers with limited privileges and resources to contain potential DoS impacts. 7. Educate developers and security teams about the risks of uncontrolled resource consumption vulnerabilities and encourage secure coding practices for parsers. 8. Maintain comprehensive logging and monitoring to detect early signs of exploitation attempts or abnormal memory usage.