Bug 2570826 (CVE-2026-126048)

Summary: CVE-2026-126048 gwenhywfar: Gwenhywfar: Denial of Service via stack-based buffer overflow during TLV parsing
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
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Priority: medium    
Version: unspecifiedKeywords: Security
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OS: Linux   
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A flaw was found in Gwenhywfar. A stack-based buffer overflow in the Type-Length-Value (TLV) parser allows an attacker to cause a Denial of Service (DoS). By supplying specially crafted records with excessive tag continuation bytes or truncated tags, such as through a malicious smart card, an attacker can cause memory corruption that crashes the application.
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Description OSIDB Bzimport 2026-11-10 20:24:57 UTC 
Gwenhywfar 4.99.8beta before 5.14.2 contains a stack-based buffer overflow in GWEN_TLV_Buffer_To_DB() in src/parser/tlv.c when decoding BER-TLV tags into a fixed 128-byte buffer. Attackers can supply a record with about 127 or more tag continuation bytes or a truncated multi-byte tag, such as via a malicious chip card's EF_SSD file read by libchipcard's ZKA driver, to crash the application.