{"id":"CVE-2026-126048","state":"PUBLISHED","title":"Gwenhywfar 4.99.8beta before 5.14.2 Stack Buffer Overflow via GWEN_TLV_Buffer_To_DB()","description":"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.","publishedAt":"2026-11-10T16:58:03.611Z","updatedAt":"2026-11-10T16:58:03.611Z","severity":{"score":5.1,"label":"Medium","version":"4.0","vector":"CVSS:4.0/AV:P/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","source":"VulnCheck"},"assigner":"VulnCheck","products":["Martin Preuss Gwenhywfar"],"affected":[{"vendor":"Martin Preuss","product":"Gwenhywfar","packageURL":"pkg:github/aqbanking/gwenhywfar","defaultStatus":"unaffected","versions":[{"version":"4.99.8beta","status":"affected","lessThan":"5.14.2","versionType":"custom"}],"repo":"https://github.com/aqbanking/gwenhywfar"}],"references":["https://github.com/aqbanking/gwenhywfar/commit/ed8e2f8cdc27fd5c1b629cf9c1f6b93b2e009757","https://github.com/aqbanking/gwenhywfar/commit/6b50388e6b4a96f02d3d56e1d7747405fa881f39","https://www.aquamaniac.de/rdm/projects/gwenhywfar/files","https://github.com/aqbanking/gwenhywfar/blob/424949d0c6e61028eaccd6e46e4c0c41931c2b2f/src/parser/tlv.c#L629-L655","https://www.vulncheck.com/advisories/gwenhywfar-4.99-8beta-before-5.14.2-stack-buffer-overflow-via-gwen-tlv-buffer-to-db"],"weaknesses":["CWE-121"],"ingestedAt":"2026-11-10T17:08:07.291Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/126xxx/CVE-2026-126048.json","commit":"c014ea22156f144a220e560a1a0daba0b213cb30","baselineCommit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-126048","state":"PUBLISHED","datePublished":"2026-11-10T16:58:03.611Z","dateUpdated":"2026-11-10T16:58:03.611Z","assignerShortName":"VulnCheck","assignerOrgId":"83251b91-4cc7-4094-a5c7-464a1b83ea10","dateReserved":"2026-11-10T16:53:12.633Z"},"containers":{"cna":{"title":"Gwenhywfar 4.99.8beta before 5.14.2 Stack Buffer Overflow via GWEN_TLV_Buffer_To_DB()","descriptions":[{"lang":"en","value":"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."}],"affected":[{"vendor":"Martin Preuss","product":"Gwenhywfar","packageURL":"pkg:github/aqbanking/gwenhywfar","defaultStatus":"unaffected","versions":[{"version":"4.99.8beta","status":"affected","lessThan":"5.14.2","versionType":"custom"}],"repo":"https://github.com/aqbanking/gwenhywfar"}],"references":[{"url":"https://github.com/aqbanking/gwenhywfar/commit/ed8e2f8cdc27fd5c1b629cf9c1f6b93b2e009757","tags":["patch"]},{"url":"https://github.com/aqbanking/gwenhywfar/commit/6b50388e6b4a96f02d3d56e1d7747405fa881f39","tags":["patch"]},{"url":"https://www.aquamaniac.de/rdm/projects/gwenhywfar/files","tags":["product"]},{"url":"https://github.com/aqbanking/gwenhywfar/blob/424949d0c6e61028eaccd6e46e4c0c41931c2b2f/src/parser/tlv.c#L629-L655","tags":["technical-description"]},{"url":"https://www.vulncheck.com/advisories/gwenhywfar-4.99-8beta-before-5.14.2-stack-buffer-overflow-via-gwen-tlv-buffer-to-db","name":"VulnCheck Advisory: Gwenhywfar 4.99.8beta before 5.14.2 Stack Buffer Overflow via GWEN_TLV_Buffer_To_DB()","tags":["third-party-advisory"]}],"metrics":[{"format":"CVSS","cvssV4_0":{"version":"4.0","vectorString":"CVSS:4.0/AV:P/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","attackVector":"PHYSICAL","attackComplexity":"LOW","attackRequirements":"NONE","privilegesRequired":"NONE","userInteraction":"NONE","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"NONE","vulnAvailabilityImpact":"HIGH","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","baseScore":5.1,"baseSeverity":"MEDIUM"}},{"format":"CVSS","cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","attackVector":"PHYSICAL","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH","baseScore":4.6,"baseSeverity":"MEDIUM"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-121","lang":"en","description":"Stack-based Buffer Overflow","type":"CWE"}]}],"providerMetadata":{"shortName":"VulnCheck","orgId":"83251b91-4cc7-4094-a5c7-464a1b83ea10","dateUpdated":"2026-11-10T16:58:03.611Z"},"datePublic":"2026-11-09T00:00:00.000Z","credits":[{"lang":"en","value":"Deus Rex","type":"finder"}],"x_generator":{"engine":"vulncheck-endgame"}}}}}