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        "cveId": "CVE-2026-0819",
        "assignerOrgId": "50d2cd11-d01a-48ed-9441-5bfce9d63b27",
        "state": "PUBLISHED",
        "assignerShortName": "wolfSSL",
        "dateReserved": "2026-01-09T17:04:43.340Z",
        "datePublished": "2026-03-19T16:54:33.442Z",
        "dateUpdated": "2026-03-19T17:19:37.134Z"
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                "orgId": "50d2cd11-d01a-48ed-9441-5bfce9d63b27",
                "shortName": "wolfSSL",
                "dateUpdated": "2026-03-19T16:54:33.442Z"
            },
            "title": "Stack buffer overflow in PKCS7 SignedData encoding with custom signed attributes",
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                {
                    "descriptions": [
                        {
                            "lang": "en",
                            "cweId": "CWE-121",
                            "description": "CWE-121: Stack-based Buffer Overflow",
                            "type": "CWE"
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                    ]
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                    "descriptions": [
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                            "lang": "en",
                            "cweId": "CWE-787",
                            "description": "CWE-787: Out-of-bounds Write",
                            "type": "CWE"
                        }
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                }
            ],
            "impacts": [
                {
                    "descriptions": [
                        {
                            "lang": "en",
                            "value": "Overflow Buffers"
                        }
                    ]
                }
            ],
            "affected": [
                {
                    "vendor": "wolfSSL",
                    "product": "wolfSSL",
                    "repo": "https://github.com/wolfSSL/wolfssl",
                    "modules": [
                        "wolfcrypt PKCS7"
                    ],
                    "programFiles": [
                        "wolfcrypt/src/pkcs7.c"
                    ],
                    "programRoutines": [
                        {
                            "name": "wc_PKCS7_EncodeSignedData()"
                        }
                    ],
                    "versions": [
                        {
                            "status": "affected",
                            "version": "5.5.0",
                            "lessThan": "5.9.0",
                            "versionType": "semver"
                        }
                    ],
                    "defaultStatus": "unaffected"
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            ],
            "descriptions": [
                {
                    "lang": "en",
                    "value": "A stack buffer overflow vulnerability exists in wolfSSL's PKCS7 SignedData encoding functionality. In wc_PKCS7_BuildSignedAttributes(), when adding custom signed attributes, the code passes an incorrect capacity value (esd->signedAttribsCount) to EncodeAttributes() instead of the remaining available space in the fixed-size signedAttribs[7] array. When an application sets pkcs7->signedAttribsSz to a value greater than MAX_SIGNED_ATTRIBS_SZ (default 7) minus the number of default attributes already added, EncodeAttributes() writes beyond the array bounds, causing stack memory corruption. In WOLFSSL_SMALL_STACK builds, this becomes heap corruption. Exploitation requires an application that allows untrusted input to control the signedAttribs array size when calling wc_PKCS7_EncodeSignedData() or related signing functions.",
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                            "value": "<p>A stack buffer overflow vulnerability exists in wolfSSL's PKCS7 SignedData encoding functionality. In wc_PKCS7_BuildSignedAttributes(), when adding custom signed attributes, the code passes an incorrect capacity value (esd-&gt;signedAttribsCount) to EncodeAttributes() instead of the remaining available space in the fixed-size signedAttribs[7] array. When an application sets pkcs7-&gt;signedAttribsSz to a value greater than MAX_SIGNED_ATTRIBS_SZ (default 7) minus the number of default attributes already added, EncodeAttributes() writes beyond the array bounds, causing stack memory corruption. In WOLFSSL_SMALL_STACK builds, this becomes heap corruption. Exploitation requires an application that allows untrusted input to control the signedAttribs array size when calling wc_PKCS7_EncodeSignedData() or related signing functions.</p>"
                        }
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://github.com/wolfSSL/wolfssl/pull/9630",
                    "name": "GitHub Pull Request"
                }
            ],
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                            "value": "GENERAL"
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                        "attackVector": "LOCAL",
                        "attackComplexity": "LOW",
                        "attackRequirements": "PRESENT",
                        "privilegesRequired": "NONE",
                        "userInteraction": "NONE",
                        "vulnConfidentialityImpact": "NONE",
                        "subConfidentialityImpact": "NONE",
                        "vulnIntegrityImpact": "HIGH",
                        "subIntegrityImpact": "NONE",
                        "vulnAvailabilityImpact": "HIGH",
                        "subAvailabilityImpact": "NONE",
                        "exploitMaturity": "UNREPORTED",
                        "Safety": "NOT_DEFINED",
                        "Automatable": "NOT_DEFINED",
                        "Recovery": "NOT_DEFINED",
                        "valueDensity": "NOT_DEFINED",
                        "vulnerabilityResponseEffort": "NOT_DEFINED",
                        "providerUrgency": "NOT_DEFINED",
                        "version": "4.0",
                        "baseSeverity": "LOW",
                        "baseScore": 2.2,
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            "workarounds": [
                {
                    "lang": "en",
                    "value": "Ensure that applications using wolfSSL PKCS7 signing functionality validate and limit the number of custom signed attributes (signedAttribsSz) to no more than MAX_SIGNED_ATTRIBS_SZ (default 7) minus the number of default signed attributes enabled. Do not allow untrusted input to control the signedAttribs array or its size.",
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                            "value": "<p>Ensure that applications using wolfSSL PKCS7 signing functionality validate and limit the number of custom signed attributes (signedAttribsSz) to no more than MAX_SIGNED_ATTRIBS_SZ (default 7) minus the number of default signed attributes enabled. Do not allow untrusted input to control the signedAttribs array or its size.</p>"
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                    ]
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            ],
            "solutions": [
                {
                    "lang": "en",
                    "value": "Update to the patched version of wolfSSL. The fix adds proper bounds checking in wc_PKCS7_BuildSignedAttributes() to validate that the number of custom signed attributes does not exceed the available space in the fixed-size signedAttribs array, returning BUFFER_E if the limit is exceeded.",
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                            "value": "<p>Update to the patched version of wolfSSL. The fix adds proper bounds checking in wc_PKCS7_BuildSignedAttributes() to validate that the number of custom signed attributes does not exceed the available space in the fixed-size signedAttribs array, returning BUFFER_E if the limit is exceeded.</p>"
                        }
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            ],
            "credits": [
                {
                    "lang": "en",
                    "value": "Maor Caplan",
                    "type": "finder"
                }
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            "source": {
                "discovery": "EXTERNAL"
            },
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                            "type": "ssvc",
                            "content": {
                                "timestamp": "2026-03-19T17:19:26.928139Z",
                                "id": "CVE-2026-0819",
                                "options": [
                                    {
                                        "Exploitation": "none"
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                                        "Automatable": "no"
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                                        "Technical Impact": "total"
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                                "role": "CISA Coordinator",
                                "version": "2.0.3"
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                "title": "CISA ADP Vulnrichment",
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