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    "cveMetadata": {
        "cveId": "CVE-2026-62381",
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        "state": "PUBLISHED",
        "assignerShortName": "VulnCheck",
        "dateReserved": "2026-07-13T22:40:54.412Z",
        "datePublished": "2026-08-22T12:26:44.558Z",
        "dateUpdated": "2026-08-22T12:26:44.558Z"
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                "dateUpdated": "2026-08-22T12:26:44.558Z"
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            "datePublic": "2026-08-07T00:00:00.000Z",
            "title": "luci-lib-px5g 2040-bit Certificate Signing Heap Buffer Overflow",
            "descriptions": [
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                    "lang": "en",
                    "value": "luci-lib-px5g (LuCI) contains a heap-based buffer overflow in the native ASN.1 encoding routine asn1_add_obj (x509write.c) when signing a certificate with a 2040-bit RSA key. For a 255-byte signature, the BIT STRING allocation is computed from the DER length encoding of 255 bytes, but the payload written after prepending the unused-bits byte is 256 bytes, requiring one additional DER length octet. As a result the allocation is 259 bytes while the tag, length, unused-bits byte, and signature require 260 bytes, and the final memcpy writes one byte beyond the heap buffer. The overflow is reachable through the exported Lua interface via create_selfsigned(); whether it is remotely exploitable depends on the embedding application. The vulnerable code is present on the openwrt-18.06 through openwrt-25.12 release branches and is absent from master, where the luci-lib-px5g package has been removed rather than patched."
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                    "descriptions": [
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                            "lang": "en",
                            "description": "Heap-based Buffer Overflow",
                            "cweId": "CWE-122",
                            "type": "CWE"
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            "affected": [
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                    "vendor": "openwrt",
                    "product": "luci",
                    "defaultStatus": "unaffected",
                    "packageName": "luci-lib-px5g",
                    "collectionURL": "https://github.com/openwrt/luci",
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