{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-4395",
        "assignerOrgId": "50d2cd11-d01a-48ed-9441-5bfce9d63b27",
        "state": "PUBLISHED",
        "assignerShortName": "wolfSSL",
        "dateReserved": "2026-03-18T15:49:41.133Z",
        "datePublished": "2026-03-19T20:41:55.642Z",
        "dateUpdated": "2026-03-20T17:09:33.816Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "50d2cd11-d01a-48ed-9441-5bfce9d63b27",
                "shortName": "wolfSSL",
                "dateUpdated": "2026-03-19T20:41:55.642Z"
            },
            "title": "Heap-based buffer overflow in wc_ecc_import_x963_ex KCAPI path",
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "lang": "en",
                            "cweId": "CWE-122",
                            "description": "CWE-122 Heap-based Buffer Overflow",
                            "type": "CWE"
                        }
                    ]
                }
            ],
            "impacts": [
                {
                    "capecId": "CAPEC-100",
                    "descriptions": [
                        {
                            "lang": "en",
                            "value": "CAPEC-100 Overflow Buffers"
                        }
                    ]
                }
            ],
            "affected": [
                {
                    "vendor": "wolfSSL",
                    "product": "wolfssl",
                    "platforms": [
                        "Linux"
                    ],
                    "repo": "https://github.com/wolfSSL/wolfssl",
                    "modules": [
                        "wolfcrypt ECC"
                    ],
                    "programFiles": [
                        "wolfcrypt/src/ecc.c"
                    ],
                    "programRoutines": [
                        {
                            "name": "wc_ecc_import_x963_ex"
                        }
                    ],
                    "versions": [
                        {
                            "status": "affected",
                            "version": "0",
                            "lessThanOrEqual": "5.8.4",
                            "versionType": "semver"
                        }
                    ],
                    "defaultStatus": "unaffected"
                }
            ],
            "descriptions": [
                {
                    "lang": "en",
                    "value": "Heap-based buffer overflow in the KCAPI ECC code path of wc_ecc_import_x963_ex() in wolfSSL wolfcrypt allows a remote attacker to write attacker-controlled data past the bounds of the pubkey_raw buffer via a crafted oversized EC public key point. The WOLFSSL_KCAPI_ECC code path copies the input to key->pubkey_raw (132 bytes) using XMEMCPY without a bounds check, unlike the ATECC code path which includes a length validation. This can be triggered during TLS key exchange when a malicious peer sends a crafted ECPoint in ServerKeyExchange.",
                    "supportingMedia": [
                        {
                            "type": "text/html",
                            "base64": false,
                            "value": "Heap-based buffer overflow in the KCAPI ECC code path of wc_ecc_import_x963_ex() in wolfSSL wolfcrypt allows a remote attacker to write attacker-controlled data past the bounds of the pubkey_raw buffer via a crafted oversized EC public key point. The WOLFSSL_KCAPI_ECC code path copies the input to key->pubkey_raw (132 bytes) using XMEMCPY without a bounds check, unlike the ATECC code path which includes a length validation. This can be triggered during TLS key exchange when a malicious peer sends a crafted ECPoint in ServerKeyExchange."
                        }
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://github.com/wolfSSL/wolfssl/pull/9988",
                    "tags": [
                        "patch"
                    ]
                }
            ],
            "metrics": [
                {
                    "format": "CVSS",
                    "scenarios": [
                        {
                            "lang": "en",
                            "value": "GENERAL"
                        }
                    ],
                    "cvssV4_0": {
                        "attackVector": "NETWORK",
                        "attackComplexity": "LOW",
                        "attackRequirements": "PRESENT",
                        "privilegesRequired": "NONE",
                        "userInteraction": "PASSIVE",
                        "vulnConfidentialityImpact": "LOW",
                        "subConfidentialityImpact": "NONE",
                        "vulnIntegrityImpact": "LOW",
                        "subIntegrityImpact": "NONE",
                        "vulnAvailabilityImpact": "LOW",
                        "subAvailabilityImpact": "NONE",
                        "exploitMaturity": "PROOF_OF_CONCEPT",
                        "Safety": "NOT_DEFINED",
                        "Automatable": "YES",
                        "Recovery": "USER",
                        "valueDensity": "DIFFUSE",
                        "vulnerabilityResponseEffort": "LOW",
                        "providerUrgency": "AMBER",
                        "version": "4.0",
                        "baseSeverity": "LOW",
                        "baseScore": 1.3,
                        "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P/AU:Y/R:U/V:D/RE:L/U:Amber"
                    }
                }
            ],
            "workarounds": [
                {
                    "lang": "en",
                    "value": "Build wolfSSL without WOLFSSL_KCAPI_ECC (this define is not enabled by default).",
                    "supportingMedia": [
                        {
                            "type": "text/html",
                            "base64": false,
                            "value": "Build wolfSSL without WOLFSSL_KCAPI_ECC (this define is not enabled by default)."
                        }
                    ]
                }
            ],
            "solutions": [
                {
                    "lang": "en",
                    "value": "Update to the wolfSSL version containing the fix from PR #9988, which adds a bounds check on inLen before the XMEMCPY to pubkey_raw in the KCAPI ECC code path.",
                    "supportingMedia": [
                        {
                            "type": "text/html",
                            "base64": false,
                            "value": " Update to the wolfSSL version containing the fix from PR #9988, which adds a bounds check on inLen before the XMEMCPY to pubkey_raw in the KCAPI ECC code path."
                        }
                    ]
                }
            ],
            "credits": [
                {
                    "lang": "en",
                    "value": "Haruto Kimura (Stella)",
                    "type": "finder"
                }
            ],
            "source": {
                "discovery": "EXTERNAL"
            },
            "x_generator": {
                "engine": "Vulnogram 1.0.1"
            }
        },
        "adp": [
            {
                "metrics": [
                    {
                        "other": {
                            "type": "ssvc",
                            "content": {
                                "timestamp": "2026-03-20T17:09:25.537926Z",
                                "id": "CVE-2026-4395",
                                "options": [
                                    {
                                        "Exploitation": "none"
                                    },
                                    {
                                        "Automatable": "no"
                                    },
                                    {
                                        "Technical Impact": "partial"
                                    }
                                ],
                                "role": "CISA Coordinator",
                                "version": "2.0.3"
                            }
                        }
                    }
                ],
                "title": "CISA ADP Vulnrichment",
                "providerMetadata": {
                    "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
                    "shortName": "CISA-ADP",
                    "dateUpdated": "2026-03-20T17:09:33.816Z"
                }
            }
        ]
    }
}