{"id":"CVE-2026-75615","aliases":["EUVD-2026-117600","GHSA-234q-m7gr-pcf8"],"status":"published","title":"ASN1SCC: Out-of-bounds read via unvalidated character index in ASN.1 string decoders","description":"ASN1SCC is an open source ASN.1 compiler for embedded systems. Prior to 4.7.0.1, the ACN runtime function Acn_Dec_String_CharIndex_private in asn1crt/asn1crt_encoding_acn.c and the generated uPER decoder InternalItem_string_with_alpha_decode in StgC/uper_c.stg do not validate a decoded character index before reading allowedCharSet. For string alphabets whose size is not a power of two, a crafted message can select an unused encoded index, read a small bounded window of adjacent static program constants, and return the byte as a successfully decoded character. The full 128-character IA5String alphabet is not affected. This issue is fixed in version 4.7.0.1.","severity":{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-07","score":0.00236,"percentile":0.14707,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-125","CWE-129"],"published":"2026-11-05T16:49:20Z","modified":"2026-11-05T21:32:43Z","products":[{"vendor":"esa","product":"asn1scc"}],"references":[{"url":"https://github.com/esa/asn1scc/security/advisories/GHSA-234q-m7gr-pcf8","tags":["x_refsource_CONFIRM","advisory"]},{"url":"https://github.com/esa/asn1scc/commit/fe6ab763bc60d8a2def4104c15414809b45fffd9","tags":["x_refsource_MISC","fix"]},{"url":"https://github.com/esa/asn1scc/releases/tag/4.7.0.1","tags":["x_refsource_MISC","web"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/75xxx/CVE-2026-75615.json","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-75615","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2026-75615","title":"ASN1SCC: Out-of-bounds read via unvalidated character index in ASN.1 string decoders","description":"ASN1SCC is an open source ASN.1 compiler for embedded systems. Prior to 4.7.0.1, the ACN runtime function Acn_Dec_String_CharIndex_private in asn1crt/asn1crt_encoding_acn.c and the generated uPER decoder InternalItem_string_with_alpha_decode in StgC/uper_c.stg do not validate a decoded character index before reading allowedCharSet. For string alphabets whose size is not a power of two, a crafted message can select an unused encoded index, read a small bounded window of adjacent static program constants, and return the byte as a successfully decoded character. The full 128-character IA5String alphabet is not affected. This issue is fixed in version 4.7.0.1.","status":"published","published":"2026-11-05T16:49:20.422Z","modified":"2026-11-05T16:49:20.422Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium","assessor":"cna"}],"cwes":["CWE-125","CWE-129"],"updated_at":"2026-11-05T17:53:59.468565Z"}],"euvd":[{"id":"EUVD-2026-117600","description":"ASN1SCC is an open source ASN.1 compiler for embedded systems. Prior to 4.7.0.1, the ACN runtime function Acn_Dec_String_CharIndex_private in asn1crt/asn1crt_encoding_acn.c and the generated uPER decoder InternalItem_string_with_alpha_decode in StgC/uper_c.stg do not validate a decoded character index before reading allowedCharSet. For string alphabets whose size is not a power of two, a crafted message can select an unused encoded index, read a small bounded window of adjacent static program constants, and return the byte as a successfully decoded character. The full 128-character IA5String alphabet is not affected. This issue is fixed in version 4.7.0.1.","status":"published","published":"2026-11-05T16:49:20Z","modified":"2026-11-05T16:49:20Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium"}],"updated_at":"2026-11-05T18:00:57.863749Z"}],"nvd":[{"id":"CVE-2026-75615","description":"ASN1SCC is an open source ASN.1 compiler for embedded systems. Prior to 4.7.0.1, the ACN runtime function Acn_Dec_String_CharIndex_private in asn1crt/asn1crt_encoding_acn.c and the generated uPER decoder InternalItem_string_with_alpha_decode in StgC/uper_c.stg do not validate a decoded character index before reading allowedCharSet. For string alphabets whose size is not a power of two, a crafted message can select an unused encoded index, read a small bounded window of adjacent static program constants, and return the byte as a successfully decoded character. The full 128-character IA5String alphabet is not affected. This issue is fixed in version 4.7.0.1.","status":"published","published":"2026-11-05T17:18:20.663Z","modified":"2026-11-05T17:18:20.663Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium","assessor":"secondary"}],"cwes":["CWE-125","CWE-129"],"updated_at":"2026-11-05T19:56:16.493279Z"}],"osv":[{"id":"CVE-2026-75615","title":"ASN1SCC: Out-of-bounds read via unvalidated character index in ASN.1 string decoders","description":"ASN1SCC is an open source ASN.1 compiler for embedded systems. Prior to 4.7.0.1, the ACN runtime function Acn_Dec_String_CharIndex_private in asn1crt/asn1crt_encoding_acn.c and the generated uPER decoder InternalItem_string_with_alpha_decode in StgC/uper_c.stg do not validate a decoded character index before reading allowedCharSet. For string alphabets whose size is not a power of two, a crafted message can select an unused encoded index, read a small bounded window of adjacent static program constants, and return the byte as a successfully decoded character. The full 128-character IA5String alphabet is not affected. This issue is fixed in version 4.7.0.1.","status":"published","published":"2026-11-05T16:49:20.422Z","modified":"2026-11-07T07:06:51.372449398Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium"}],"cwes":["CWE-125","CWE-129"],"updated_at":"2026-11-07T03:08:10.290242Z"}]}}