{"id":"CVE-2026-102758","state":"PUBLISHED","title":"The `_nx_secure_x509_asn1_tlv_block_parse()` function parses ASN.1 TLV (tag-length-value) blocks out of DER-encoded data. It is the primitive underneath all X.509 certificate parsi","description":"The `_nx_secure_x509_asn1_tlv_block_parse()` function parses ASN.1 TLV (tag-length-value) blocks out of DER-encoded data. It is the primitive underneath all X.509 certificate parsing in NetX Secure, and therefore runs on certificates supplied by a remote peer during the TLS handshake.\n\n\n\nThe function reads the one-byte ASN.1 tag from the caller's buffer *before* checking that the buffer holds at least one byte. When a caller passes a remaining length of zero, the guard correctly returns `NX_SECURE_X509_ASN1_LENGTH_TOO_LONG`, but the read has already happened one byte past the end of the buffer.\n\n\n\ncode:\n\n\n\nnx_secure/src/nx_secure_x509_asn1_tlv_block_parse.c\n\n\n\n```\n\n\n\nUINT _nx_secure_x509_asn1_tlv_block_parse(const UCHAR *buffer, ULONG *buffer_length, USHORT *tlv_type,\n\n                                          USHORT *tlv_tag_class, ULONG *tlv_length,\n                                          const UCHAR **tlv_data, ULONG *header_length)\n\n\n{\n\n\n\nUINT   current_index;\n\n\n\nUSHORT current_tag;\n\n\n\nULONG  length;\n\n\n\nULONG  length_bytes;\n\n    current_index = 0;\n    current_tag = buffer[current_index];      /* <-- read before the bounds check */\n    if (*buffer_length < 1)\n    {\n        return(NX_SECURE_X509_ASN1_LENGTH_TOO_LONG);\n    }\n\n\n```\n\n\n\nThe remainder of the function is correctly ordered. The multi-byte length path is guarded by `length_bytes > 4 || length_bytes > *buffer_length` before its read loop, the decoded value is checked against `length > *buffer_length`, and the second single-byte length read follows its own `*buffer_length < 1` guard. The tag read is the only load placed ahead of its check.","publishedAt":"2026-09-29T17:26:44.424Z","updatedAt":"2026-09-30T20:42:39.497Z","severity":{"score":7.5,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","source":"CISA-ADP"},"assigner":"eclipse","products":["Eclipse Foundation NetX Duo"],"affected":[{"vendor":"Eclipse Foundation","product":"NetX Duo","packageName":"NetX Duo","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThanOrEqual":"6.5.1.202602","versionType":"custom"},{"version":"6.5.2.202603","status":"unaffected"}]}],"references":["https://github.com/eclipse-threadx/netxduo/security/advisories/GHSA-f95g-xc4w-mrcr"],"weaknesses":["CWE-126"],"ingestedAt":"2026-10-29T20:10:13.529Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/102xxx/CVE-2026-102758.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-102758","state":"PUBLISHED","datePublished":"2026-09-29T17:26:44.424Z","dateUpdated":"2026-09-30T20:42:39.497Z","assignerShortName":"eclipse","assignerOrgId":"e51fbebd-6053-4e49-959f-1b94eeb69a2c","dateReserved":"2026-09-29T16:21:58.057Z"},"containers":{"cna":{"descriptions":[{"lang":"en","value":"The `_nx_secure_x509_asn1_tlv_block_parse()` function parses ASN.1 TLV (tag-length-value) blocks out of DER-encoded data. It is the primitive underneath all X.509 certificate parsing in NetX Secure, and therefore runs on certificates supplied by a remote peer during the TLS handshake.\n\n\n\nThe function reads the one-byte ASN.1 tag from the caller's buffer *before* checking that the buffer holds at least one byte. When a caller passes a remaining length of zero, the guard correctly returns `NX_SECURE_X509_ASN1_LENGTH_TOO_LONG`, but the read has already happened one byte past the end of the buffer.\n\n\n\ncode:\n\n\n\nnx_secure/src/nx_secure_x509_asn1_tlv_block_parse.c\n\n\n\n```\n\n\n\nUINT _nx_secure_x509_asn1_tlv_block_parse(const UCHAR *buffer, ULONG *buffer_length, USHORT *tlv_type,\n\n                                          USHORT *tlv_tag_class, ULONG *tlv_length,\n                                          const UCHAR **tlv_data, ULONG *header_length)\n\n\n{\n\n\n\nUINT   current_index;\n\n\n\nUSHORT current_tag;\n\n\n\nULONG  length;\n\n\n\nULONG  length_bytes;\n\n    current_index = 0;\n    current_tag = buffer[current_index];      /* <-- read before the bounds check */\n    if (*buffer_length < 1)\n    {\n        return(NX_SECURE_X509_ASN1_LENGTH_TOO_LONG);\n    }\n\n\n```\n\n\n\nThe remainder of the function is correctly ordered. The multi-byte length path is guarded by `length_bytes > 4 || length_bytes > *buffer_length` before its read loop, the decoded value is checked against `length > *buffer_length`, and the second single-byte length read follows its own `*buffer_length < 1` guard. The tag read is the only load placed ahead of its check."}],"affected":[{"vendor":"Eclipse Foundation","product":"NetX Duo","packageName":"NetX Duo","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThanOrEqual":"6.5.1.202602","versionType":"custom"},{"version":"6.5.2.202603","status":"unaffected"}]}],"references":[{"url":"https://github.com/eclipse-threadx/netxduo/security/advisories/GHSA-f95g-xc4w-mrcr"}],"problemTypes":[{"descriptions":[{"cweId":"CWE-126","lang":"en","description":"CWE-126 Buffer Over-read","type":"CWE"}]}],"providerMetadata":{"shortName":"eclipse","orgId":"e51fbebd-6053-4e49-959f-1b94eeb69a2c","dateUpdated":"2026-09-29T17:26:44.424Z"},"credits":[{"lang":"en","value":"tinic","type":"finder"}],"source":{"discovery":"UNKNOWN"},"x_generator":{"engine":"Vulnogram 1.0.5"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"cvssV3_1":{"scope":"UNCHANGED","version":"3.1","baseScore":7.5,"attackVector":"NETWORK","baseSeverity":"HIGH","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","integrityImpact":"NONE","userInteraction":"NONE","attackComplexity":"LOW","availabilityImpact":"HIGH","privilegesRequired":"NONE","confidentialityImpact":"NONE"}},{"other":{"type":"ssvc","content":{"timestamp":"2026-09-30T20:42:14.455455Z","id":"CVE-2026-102758","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-09-30T20:42:39.497Z"}}]}}}