static int check_issued(X509_STORE_CTX *ctx, X509 *x, X509 *issuer)
{
    int ret;
    if (x == issuer)
        return cert_self_signed(x);
    ret = X509_check_issued(issuer, x);
    if (ret == X509_V_OK) {
        int i;
        X509 *ch;
        /* Special case: single self signed certificate */
        if (cert_self_signed(x) && sk_X509_num(ctx->chain) == 1)
            return 1;
        for (i = 0; i < sk_X509_num(ctx->chain); i++) {
            ch = sk_X509_value(ctx->chain, i);
            if (ch == issuer || !X509_cmp(ch, issuer)) {
                ret = X509_V_ERR_PATH_LOOP;
                break;
            }
        }
    }

    if (ret == X509_V_OK)
        return 1;
    /* If we haven't asked for issuer errors don't set ctx */
    if (!(ctx->param->flags & X509_V_FLAG_CB_ISSUER_CHECK))
        return 0;

    ctx->error = ret;
    ctx->current_cert = x;
    ctx->current_issuer = issuer;
    return ctx->verify_cb(0, ctx);
}

The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.