{"id":65820,"date":"2025-08-29T09:54:49","date_gmt":"2025-08-29T09:54:49","guid":{"rendered":""},"modified":"2025-08-31T15:10:01","modified_gmt":"2025-08-31T21:10:01","slug":"cve-2025-55398-critical-integer-constraint-vulnerability-in-asn1c","status":"publish","type":"post","link":"https:\/\/www.ameeba.com\/blog\/cve-2025-55398-critical-integer-constraint-vulnerability-in-asn1c\/","title":{"rendered":"CVE-2025-55398: Critical Integer Constraint Vulnerability in asn1c<\/strong>"},"content":{"rendered":"

Overview<\/strong><\/p>\n

In a recent discovery, a critical vulnerability, CVE-2025-55398, was identified in the mouse07410 asn1c through 0.9.29, a fork of vlm asn1c. This vulnerability may affect a range of applications and services using this version of asn1c for encoding and decoding ASN.1 data structures. ASN.1 (Abstract Syntax Notation One) is widely used in telecommunications and computer networking, and thus the vulnerability potentially<\/a> has a broad impact.
\nThe issue lies in the UPER (Unaligned Packed Encoding Rules), where asn1c-generated decoders fail to enforce INTEGER constraints when the bound is positive and exceeds 32 bits in length. This could potentially allow incorrect or malicious input to be processed, leading to serious consequences like system compromise<\/a> or data leakage.<\/p>\n

Vulnerability Summary<\/strong><\/p>\n

CVE ID: CVE-2025-55398
\nSeverity: Critical (9.8 – CVSS Severity Score)
\nAttack Vector: Direct (via malformed ASN.1 data)
\nPrivileges Required: None
\nUser Interaction: None
\nImpact: System compromise<\/a>, Data leakage<\/p>\n

Affected Products<\/strong><\/p>

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