A stack buffer overflow exists in wolfSSL's PKCS7 implementation in the wcPKCS7DecryptOri() function in wolfcrypt/src/pkcs7.c. When processing a CMS EnvelopedData message containing an OtherRecipientInfo (ORI) recipient, the function copies an ASN.1-parsed OID into a fixed 32-byte stack buffer (oriOID[MAXOIDSZ]) via XMEMCPY without first validating that the parsed OID length does not exceed MAXOIDSZ. A crafted CMS EnvelopedData message with an ORI recipient containing an OID longer than 32 bytes triggers a stack buffer overflow. Exploitation requires the library to be built with --enable-pkcs7 (disabled by default) and the application to have registered an ORI decrypt callback via wcPKCS7SetOriDecryptCb().
{
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/5xxx/CVE-2026-5295.json",
"cwe_ids": [
"CWE-121"
],
"cna_assigner": "wolfSSL"
}{
"extracted_events": [
{
"introduced": "0"
},
{
"fixed": "5.9.1"
}
],
"source": [
"AFFECTED_FIELD",
"CPE_RANGE"
],
"cpe": "cpe:2.3:a:wolfssl:wolfssl:*:*:*:*:*:*:*:*"
}